Hey! Hey!Hey!
Hey! Hey!
Hey!
Hey!
Hey!Hey!
Hey!Hey!
Hey! Hey!
Hey! Hey!
Hay
Today TodayToday
Today!!!!!!!!!
We will be working on
solving system of equations by elimination !
BUT FIRST !!!!
RANDOM DANCE PARTY
!!!!!!
Okay now we’re ready to work
:D haha
But first.
We’re going to need to know a few things
aren’t we?
(this is where you say yes and nod your head so
Mrs. Austin thinks your smart and are
Paying attention)
How do you solve a system of equations
using elimination??
It’s actually a whole lot easier than you think.
So let’s get started!!!! HEY STOP
DANCING!!! >:(
Okay. Here’s our problem
2x + y = 93x – y = 16
Note that, if I add down, the y's will cancel out. So I'll draw an "equals"
bar under the system,
and add down
Then I get this.2x + y = 93x – y = 165x = 25
Now I can divide through to solve for
x = 5, and then back-
solve, using either of the original
equations, to find the value of y. The first equation
has smaller numbers,
so I'll back-solve in that one:2(5) + y = 9
10 + y = 9 y = –1
Then the solution is…..
RAVE DANCE TIME!!!
Haha!! Just Kidding!!!
(x, y) = (5, –1).
(x, y)
= (5, –
1).
(x, y) = (5, –
1).(x, y) = (5, –
1).
(x, y) = (5, –1).
(x, y)
= (
5,
–1
).
(x, y) = (5, –
1).
(x, y
) = (5
, –
1).
Some of you may bewondering what would
happen if I use the other equation.It doesn't matter which equation you use for the backsolving;
you'll get the same answer either way. If I'd used the second equation, I'd have gotten:
3(5) – y = 16 15 – y = 16 –y = 1
y = –1
...which is the same result as before.
Now…How is this all usedIn the real world?
Of course silly!When you become a
Algebra One teacher likeMrs. Austin.
Thank you for listening toMy presentation
But of course we can’t go Without one last thing….
DANCE PARTY!!!!!!
AND JUST TO GIVE YOU NIGHTMARES!!!!
End.