By: Anna Smoak Multiplying Polynomials Slide 2 10 inches7 3 6
inches 3 How many different ways can you find the area of the large
rectangle? Warm Up: Slide 3 10 inches 7 3 6 inches 3 Method: A=LxW
A=10 in x 6 in A=60 in 2 Method: Area of large rectangle=The sum of
the area of all the smaller triangles A=(3 in)(3 in)+(3 in)(7 in) +
(3 in)(3 in) + (3 in)(7in) A=9 in 2 + 21 in 2 + 9 in 2 + 21 in 2
A=60 in 2 Method: Area of large rectangle=The sum of the area of
two smaller rectangles A=3 in(3 in +7 in) + 3 in(3 in +7 in) A=9 in
2 + 21 in 2 + 9 in 2 + 21 in 2 A=60 in 2 OR A=7 in(3 in + 3 in) + 3
in(3 in + 3 in) A=21 in 2 + 21 in 2 + 9 in 2 + 9 in 2 A=60 in 2
Slide 4 x + 2 2x x + 1 x 1 How many different ways can you find the
area of the large rectangle? Slide 5 x + 2 2x x + 1 x 1 x2x2 2x x2
But this is the same as distributing (x + 1)(x + 2) = x ( x + 2) +
1 (x + 2) = x 2 + 2x + 1x + 2 = x 2 + 3x + 2 To find the total area
we can find the sum of the smaller areas. (x + 1)(x + 2) = (x)(x) +
(x)(2) + (1)(x) + (1)(2) = x 2 + 2x + 1x + 2 = x 2 + 3x + 2 Find:
(x + 1)(x + 2) Slide 6 x - 5 -5x x + 3 x 3 x2x2 2x x2 But this is
the same as distributing as well (x + 3)(x - 5) = x (x 5) + 3 (x 5)
= x 2 - 5x + 3x - 15 = x 2 - 2x - 15 To find the total area we can
find the sum of two smaller areas. x(x 5) + 3 (x 5)= x 2 5x + 3x
15= x 2 2x 15 Find: (x + 3)(x - 5) Slide 7 Simplify (x + 3)(x 2)
(Using the distributive property) x(x - 2) + 3 (x - 2) Distribute
the first binomial to the second x 2 - 2x + 3x - 6 Use the
distributive property to multiply x 2 + x - 6 Add the like terms
Slide 8 WORK IN PAIRS How would you simplify the expression (3x +
4)(5x 2 4x + 6)? Distribute the binomial to the trinomial 3x(5x 2
4x + 6) + 4 (5x 2 4x + 6) = Use the distributive property to
multiply 15x 3 12x 2 + 18x + 20x 2 16x + 24 = Add the like terms
15x 3 + 8x 2 + 2x + 24 Slide 9 WORK IN PAIRS Simplify : (2y 2 + 7y
5)(3y 2 5y + 4) Slide 10 TICKET OUT OF THE DOOR Find the area of a
triangle with base 2x + 3 and height 3x 1.
