Question

Solve the following system of equations by using the substitution method.
3y – 2x = 11
y + 2x = 9

Answer 1

how would i do this?

Answer 2

You first want to cancel terms, that is, isolate y. Substitution, like elimination, is a method for solving a system of equations. You want to add both the equations together, so that x cancels out. In this equation, we already see +2 and -2 will cancel when added.

3y – 2x = 11
y + 2x = 9

=

4y = 20.

You see, the 2s canceled, 3y + y = 4y, and 11 + 9 = 20.

Now solve for y by dividing.

y = 5.

Alright, now take y = 5 and plug it into either equation. I'll choose the second one.

y + 2x = 9
5 + 2x = 9
2x = 14
x = 7.

So now we know what x equals, and so far we have (7, y)

Now plug x into the equation to solve for y.

y + 2x = 9
y + 2(7) = 9
y + 14 = 9
y = -5

Thus: (7, -5)

Hope this helped ~

Answer 3

thx sooo much!

Answer 4

this will help me solve the next 20q :D