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ame:______________________________ Date:__________ The Parallelogram REMEMBER A parallelogram is a quadrilateral with opposite sides parallel. It has many special properties. If you are given parallelogram ABCD then: Property Meaning (1) opposite sides are parallel (1) AB ll DC, AD ll BC (2) opposite sides are congruent (2) ABDC, ADBC (3) opposite angles are congruent (3) <A<C, <D<B (4) consecutive angles are supplementary (4) m<A + m<B =180 m<B + m<C =180 m<C + m<D =180 m<D + m<A = 180 If the diagonals are drawn then: (5) the diagonals bisect each other (5) AEEC, DEEB 1. In parallelogram ABCD, m < B = 60. Find m < C. 4.In parallelogram ABCD, m<D=(6x+40) and m<B=(4x+70). Find the value of m<B. 2. In parallelogram PQRS, the ratio of measure of <Q to the measure of <R 1:5. Find m<Q. 5. Which statement is not true for every given parallelogram PQRS? (1) PQSR (3)PR is perpendicular to SQ (2)<P<R (4)m<P + m<S =180 3. In parallelogram CDEF, CD=(5x-6) and FE=(3x+8). Find the value of CD. 6. In parallelogram QRST, diagonals QS and RT intersect at point E. If is QE=4x+3 and ES=23, find the value of QE and x.

The Parallelogram - Weebly · The Parallelogram REMEMBER A parallelogram is a quadrilateral with opposite sides parallel. It has many special properties. ... m

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Page 1: The Parallelogram - Weebly · The Parallelogram REMEMBER A parallelogram is a quadrilateral with opposite sides parallel. It has many special properties. ... m

Name:______________________________ Date:__________

The Parallelogram REMEMBER A parallelogram is a quadrilateral with opposite sides parallel. It has many special properties. If you are given parallelogram ABCD then: Property Meaning (1) opposite sides are parallel (1) AB ll DC, AD ll BC

(2) opposite sides are congruent (2) AB≅DC, AD≅BC

(3) opposite angles are congruent (3) <A≅<C, <D≅<B (4) consecutive angles are supplementary (4) m<A + m<B =180 m<B + m<C =180 m<C + m<D =180 m<D + m<A = 180 If the diagonals are drawn then:

(5) the diagonals bisect each other (5) AE≅EC, DE≅EB

1. In parallelogram ABCD, m < B = 60. Find m < C.              

4.In parallelogram ABCD, m<D=(6x+40) and m<B=(4x+70). Find the value of m<B.

2. In parallelogram PQRS, the ratio of measure of <Q to the measure of <R 1:5. Find m<Q.  

5. Which statement is not true for every given parallelogram PQRS? (1) PQ≅SR (3)PR is perpendicular to SQ (2)<P≅<R (4)m<P + m<S =180  

3. In parallelogram CDEF, CD=(5x-6) and FE=(3x+8). Find the value of CD.

 

6. In parallelogram QRST, diagonals QS and RT intersect at point E. If is QE=4x+3 and ES=23, find the value of QE and x.

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7. In parallelogram ABCD, the measures of angles A and B are in the ratio of 1:8. Find m<B.  

12. In the accompanying diagram of parallelogram ABCD, DF is perpendicular to diagonal AC at point F. If m<CAB=34, find m<CDF.  

8.The measures of two opposite angles of a parallelogram are represented by 5x + 40 and 3x+50. Find x.

13. In parallelogram ABCD, m<A=(3x+40) and m<C=(7x-100). Find the measure in degrees of <D.  

9. Which statement is always true? (1) The diagonals of a parallelogram are congruent (2) The diagonals of a parallelogram bisect the angle of the parallelogram (3) The diagonals of a parallelogram bisect each other. (4) The diagonals of a parallelogram are perpendicular to each other.  

14. In parallelogram ABCD, diagonal AC is drawn. If m<D=110 and m<CAD=50, find m<CAB.            

10. In parallelogram ABCD, diagonals AC and BD intersect at point E. (1) AC ┴DB (2) ΔDEC≅ΔAEB (3) ΔABD≅ΔAED (4) ΔBEC≅ΔDEC  

15. In parallelogram PQRS, diagonal PR is drawn. If m<S=100 and m<SRP=40, then which of the following statements must be true? (1) SR>SP (2) SP>SR (3) SP=SR (4) PR is the smallest side of ΔPRS  

11. In the accompanying diagram, side AB of parallelogram ABCD is extended to E. If m<CBE=35, find m<D.

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Name:______________________________ Date:_______

Quadrilateral NOTES A ____________ is a polygon with 4 sides. The SUM of the 4 angles is 360. I) ___________________ Properties of a ________________: a) Opposite sides are ___________. b) Opposite ________ are congruent. c) Opposite ________ are congruent. d) Consecutive angles are __________________. e) The diagonals _________ each other. Note: A diagonal divides a parallelogram into 2 congruent triangles. Examples: 1) If one angle of a parallelogram measures 55, then find the measures of the other 3 angles. 2) In parallelogram ABCD, m<A = 2x - 20 and m<C = 5x - 80. Find the value of <A. 3) In parallelogram FGHI, m<F:m<G = 2:7. Find the measure of <H.

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Name:______________________________ Date:____________

Aim: To prove a quadrilateral is a parallelogram

DO NOW Without looking at your notes or homework, try to list all

the properties of a parallelogram (There are 5 Properties)

1. _______________________________________ 2. _______________________________________ 3. _______________________________________ 4. _______________________________________ 5. _______________________________________

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Proving a Quadrilateral is a Parallelogram . *You can be asked to prove a Parallelogram by either coordinate geometry or statement/reason. Six ways to prove a quadrilateral is a parallelogram: In a parallelogram, 1. ________________________________________________________________ (Coordinate Geometry:_______________________________________________) 2. ________________________________________________________________ (Coordinate Geometry:_______________________________________________) 3. ________________________________________________________________ (Coordinate Geometry:_______________________________________________) 4. ________________________________________________________________ (Coordinate Geometry:_______________________________________________) 5. ________________________________________________________________ (Coordinate Geometry:_______________________________________________) 6. ________________________________________________________________ (Coordinate Geometry:_______________________________________________)

Page 6: The Parallelogram - Weebly · The Parallelogram REMEMBER A parallelogram is a quadrilateral with opposite sides parallel. It has many special properties. ... m

Name:______________________________ Date:_______

Proving  Quadrilaterals  are  Parallelograms  

1)  The  coordinates  of  three  points  in  the  coordinate  plane  are  A(-­‐2,-­‐3),  B(5,-­‐3)  and  C(2,2).    

a) Find  the  coordinates  of  D  if  ABCD                is  a  parallelogram.        b) By  COORDINATE  GEOMETRY,                  prove  that  ABCD  is  a  parallelogram.  

     2)  Given:  PQRS  is  a  parallelogram  with  PT≅RM            Prove:  TQMS  is  a  parallelogram   Statements                      Reasons  

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HOMEWORK  3)  Quadrilateral  ABCD  has  coordinates  A(-­‐1,3),  B(4,4),  C(5,-­‐3)  and  D(-­‐2,-­‐2).    Using  coordinate  geometry,  prove:    a)  the  diagonals  are  perpendicular.                  b)  ABCD  has  a  least  one  pair  of  congruent  sides.                    c)  ABCD  is  NOT  a  parallelogram.      

4)  Given:  Quadrilateral  ABCD.            FGE,  AGC,  FG≅EG,  AG≅CG  and  <B≅<D            Prove:  ABCD  is  a  parallelogram    Statements           Reasons

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Name:______________________________________ Date:____________

Aim: To define the properties of a rectangle and a rhombus. To prove a quadrilateral is a rectangle and a rhombus.

Rectangle Notes

II) Rectangle Properties: a) _______________________________________________________

b) _______________________________________________________

c) _______________________________________________________ To PROVE a quadrilateral is a rectangle:

* 1)_________________________________________________. (Coordinate Geometry:______________________________) 2) ________________________________________________.

(Coordinate Geometry:______________________________)

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Rhombus Notes III) Rhombus Properties: a) _____________________________________________ b) _____________________________________________ c) _____________________________________________ d) _____________________________________________ Proving that a Quadrilateral is a Rhombus

* 1) ________________________________________________. (Coordinate Geometry:______________________________) 2) ________________________________________________. (Coordinate Geometry:______________________________) 3) ________________________________________________. (Coordinate Geometry:______________________________)

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Name:_________________________________ Date:__________

1) The coordinates of vertices ABCD are A(-2,0), B(2,-2), C(5,4) and D(1,6). a) Graph the quadrilateral.

b) Prove that ABCD is a rectangle.

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2) The vertices of quadrilateral ABCD are A(-1,1), B(4,0), C(5,5) and D(0,6). a) Prove that ABCD is a parallelogram. b) Prove that the diagonals of ABCD are perpendicular.

c) Is ABCD a rhombus? EXPLAIN!!

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Name:_________________________________ Date:__________

The RHOMBUS REMEMBER A rhombus is a parallelogram with adjacent sides equal. In addition to having all the properties of a parallelogram, the rhombus has several other properties. If you are given rhombus ABCD then: Property Meaning (1) all properties of the (1) Refer to notes parallelogram are true

(2) all sides are congruent (2)AB≅BC≅CD≅AD (3) the diagonals bisect the opposite angles (3) m<DAC=m<BAC m<DCA=m<BCA m<ADB=m<CDB m<ABD=m<CBD

(4) the diagonals are perpendicular (4) DB┴AC at E to each other

1.  In  rhombus  ABCD,  AB=(6x-­‐3)  and  BC=(4x+7).  Find  AB.    X  =  5  AB  =  27        

5.  If  the  lengths  of  the  diagonals  of  a  rhombus  are  10  and  24,  find  the  length  of  one  side  of  the  rhombus.    

2.The  lengths  of  the  diagonals  of  a  rhombus  are  6  and  8.  What  is  the  length  of  a  side  of  a  rhombus?    Pythagorean  Theorem          

6.  In  the  accompanying  diagram  of  rhombus  ABCD,  m<ABD=50.  Find  m<A.    

3.  In  the  accompanying  diagram  of  rhombus  CDEF,  diagonal  FD  is  drawn  and  m<E=40.    Find  m<CFD.          70        

7.  Given  a  parallelogram,  a  rhombus  and  a  rectangle.    If  one  of  these  quadrilaterals  is  picked  at  random,  what  is  the  probability  that  its  diagonals  bisect  each  other?  (1)   1  (2)   2/3    (3)   1/3  (4)   0  

4.  In  rhombus  ABCD,  diagonal  DB  is  congruent  to  side  AD.  What  is  the  measure  of  <A?    60        

 

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Name:_________________________________ Date:_______

The RECTANGLE REMEMBER A rectangle is a parallelogram with a right angle. In addition to having all the properties of a parallelogram, the rectangle has several other properties. If you are given rectangle ABCD then: Property Meaning (1) all the properties of the (1) Refer to notes parallelogram are true (2) all the angles are right (2) m<A=m<B=m<C=m<D=90 and are congruent

(3) the diagonals are congruent (3) AC≅DB  

1.  In  rectangle  PQRS  with  diagonals  PR  and  SQ,  if  PR=(4x-­‐10)  and  SQ=(7x-­‐40),  find  PR.            

6.  In  rectangle  ABCD,  AD=6  and  AB=8.  What  is  the  measure  of  diagonal  AC?  

2.  In  rectangle  ABCD,  AB=4  and  BC=3.  AC  must  be  (1)  5  (2)  7  (3)  25  (4)  4        

7.  The  diagonals  of  rectangle  ABCD  intersect  at  E.    If  DE=(2x+3)  and  AE=(x+6),  find  the  value  of  AE.  

3.  In  rectangle  ABCD  diagonal  AC  is  drawn.    In  m<DCA=30,  find  m<CAD.            

8.  The  diagonals  of  rectangle  RSTV  intersect  at  Q.    If  VQ=(3x-­‐3)  and  RT=(5x-­‐1)  find  the  value  of  RT.  

4.  The  diagonals  of  rectangle  ABCD  intersect  at  E.    If  DE=(3x+1)  and  EB=(2x+7),  find  the  value  of  BE  and  ED.            

9.  The  diagonals  of  a  rectangle  must  always  be  perpendicular  to  each  other.  (True  or  False)  

5.  If  the  measure  of  one  angle  of  a  parallelogram  is  90,  what  is  the  probability  that  the  parallelogram  is  a  rectangle?            

10.  In  rectangle  ABCD,  BC=30  and  AB=40.    If  diagonals  AC  and  AB  intersect  at  E,  find  the  measure  of  BE.  

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 Name:____________________________________ Date:_________

Proofs  using  the  Properties  of  a  Rectangle  and  Rhombus  

E

1)  Given:  Rectangle  ABCD  with  E  the                                          midpoint  of  DC          Prove:  <1≅<2      Statements              Reasons

  2)  Given:  AECB  is  a  rhombus,  AED,                  FEC,  <FAB≅<DCB          Prove:  FE≅DE Statements              Reasons  

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Name:____________________________________ Date:_________ 3) In the coordinate plane A, (-1,-2), B(1,2), C(-1,3), and D(-3,-1) are the vertices of a quadrilateral. a) Find AB and CD b) Find the slope of AB and the slope of CD c) What does the answer to part b tell you about AB and CD? d) Based on the answers to a and b, explain why ABCD is a parallelogram. e) Find the slope of AD. f) What do the answers to part b and e tell you about AB and AD? g) Based on the answers to part d and f, explain why ABCD is a rectangle.

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4) In the coordinate plane, A(-1,0), B(3,-3), C(3,2), and D(-1,5) are the vertices of a quadrilateral. AC and BD intersect at M(1,1).

a) Show that AC and BD bisect each other. b) Based on the answer to part a, explain why ABCD is a parallelogram. c) Show that AC┴ BD. d) Based on the answers to parts b and c, explain why ABCD is a rhombus.

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Name:___________________________________ Date:_________ 5) Given: A(-2,2), B(6,5), C(4,0), D(-4,3) Prove: ABCD is a parallelogram but not a rectangle

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6) The vertices of quadrilateral ABCD are A(2,3), B(11,6), C(10,9), and D(1,6). a) Using coordinate geometry, show that diagonals AC and BD bisect each other b) Using coordinate geometry, show that quadrilateral ABCD is a rectangle.

Page 19: The Parallelogram - Weebly · The Parallelogram REMEMBER A parallelogram is a quadrilateral with opposite sides parallel. It has many special properties. ... m

Name:______________________________________ Date:____________

Aim: To define the properties of a square. To prove a quadrilateral is a square.

Square Notes

IV) SQUARE Properties: a) _______________________________________________________

b) _______________________________________________________ To PROVE a quadrilateral is a SQUARE: 1)_________________________________________________. 2) ________________________________________________.

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Name:___________________________________ Date:_________

The SQUARE REMEMBER A square is a rhombus with four angles or is a rectangle with four equal sides. Since it is both a rectangle and a rhombus, all the properties you have learned hold true for the square. Example: If the side of a square ABCD is 5, find the diagonal BD. Solution: AB=DA=5 sides are congruent x2=52+52 Pythagorean theorem x2=25+25 x2=50 x=√50=√25*2=5√2 ANSWER

1. In the accompanying diagram, quadrilateral ABCD is a square with diagonal DB. Which of the statements are NOT true? (1) AB≅CB

(2) AD≅CB

(3) DA⊥AB (4) AD≅DB

4. If the side of a square is 4, find the length of the diagonal.

2. Which statement is false? (1) a square is a rectangle (2) a square is a rhombus (3) a rhombus is a square (4) a square is a parallelogram

5. In the accompanying diagram CDEF is a square with diagonal CE drawn. Which statement is NOT true? (1) ΔCFE is isosceles (2) ΔCFE is a right triangle (3) ΔCFE≅ΔCDE (4) ΔCDE is equilateral

3. In the accompanying diagram, PQRS is a square with diagonal SQ. Which statement is NOT true? (1) <1≅<2

(2) <2≅<3

(3) <4≅<P

(4) <P≅<R

6. In square ABCD diagonal AC is drawn. How many degrees are there in the measure of <ACB? 7. Find the diagonal of a square whose perimeter is 28.

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1. The vertices of quadrilateral GRID are G(4,1), R(7,-3), I(11,0), and D(8,4). Using coordinate geometry, prove that quadrilateral GRID is a square.

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2. The vertices of quadrilateral ABCD are A(-1,1), B(4,5), C(9,1), and D(4,-3). Using coordinate geometry, prove that a. ABCD is a rhombus b. ABCD is NOT a square

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Name:_______________________________ Date:_____________

Trapezoid Notes

V) Trapezoid *_____________________________. (NOT_______________________) The ANGLES of the trapezoid add up to ________. Isosceles Trapezoid - ________________________________. 1)_______________________________ _______________________________. 2)____________________________________________________________. 3) ____________________________________________________________.

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Name:______________________________ Date:_______

The Trapezoid and Isosceles Trapezoid REMEMBER A trapezoid is a quadrilateral that has two and only two sides parallel. The parallel sides are called the bases and the non-parallel sides are called the legs. An isosceles trapezoid is a trapezoid, which has congruent legs. Example: Given isosceles trapezoid ABCD with AB ll CD, AB=4, CD=14, and AD=13. Find the length of an altitude of trapezoid ABCD. Solution: Draw in altitude AE and BF such that Rectangle ABFE is formed and EF=4. Since ABCD is isosceles, ΔADE can be proven to be congruent to ΔBFC and DE≅FC. Therefore, DE=FC=5. By the Pythagorean theorem x2+52=132 x2+25=169 x2=144 x=12 answer

1.In the accompanying diagram, isosceles trapezoid CDEF has bases of lengths 6 and 12 and an altitude of length 4. Find CD.

4. In the accompanying diagram, isosceles trapezoid ABCD has bases AB and DC, and diagonals AC and BD are drawn. Which statement is NOT true? (1) AD≅BC

(2) AC≅BD

(3) AB≅DC (4) AB ll DC

2.In the accompanying diagram of trapezoid ABCD, CD=10, m<A=45, m<D=90, and base BC=3. Find the length of base AD.

5. ABCD is an isosceles trapezoid with bases AB and DC. If AD=3x+4 and BC=x+12, find AD.

3.In isosceles trapezoid ABCD, AB ll CD, AB=18, CD=6 and AD=10. Find the length of an altitude of ABCD.

6. CDEF is a trapezoid with CD // FE. If m<F and m<C are in the ratio 1:4, find the measure of <F.

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In 7-12, answer true or false in each case. _____________7. In an isosceles trapezoid, nonparallel sides are congruent. _____________8.In a trapezoid, at least two sides must be congruent. _____________9. In a trapezoid, base angles are always congruent. _____________10. The diagonals of a trapezoid are congruent only if the nonparallel sides of the trapezoid are congruent. _____________11. A trapezoid is a special kind of parallelogram. _____________12. In a trapezoid, two consecutive angles that are not angles on the same base must be supplementary. In 13-16 is a trapezoid with AB//DC. When ABCD is isosceles, sides AD and BC are marked as congruent. In each case, find the measures of the angles indicated by arcs in the diagram.

13. 14. 15. 16.                        

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           17.  Quadrilateral PQRS has vertices P(-3,-4), Q(9,5), R(-1,10), and S(-5,7). Prove that quadrilateral PQRS is an isosceles trapezoid.

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18) Given: Isosceles Trapezoid ABCD with ABllDC and AD≅CB Prove: AC≅BD Statements Reasons

19

119) Given: Isosceles trapezoid GTHR with GR≅TH and diagonals GH and TR Prove: GH≅TR Statements Reasons