Question

Use complete sentences to explain in detail how you would use the substitution method to solve the following system of equations:
x = 4y

x + 2y = 12

Your description should include:

-how to find x

-how to find y

-the answer to the system

Answer 1

If we now that 4y equals to x, that means we can replace x with 4y.

Therefore we can write: 4y+2y = 12
We can summarize that to 6y = 12.
If we divide both sides with 6, you get y = 2

In order to solve for x, we can use the second equation and just replace y with value we just got (y=2).

We can write: x+2*2=12
Now you move 2*2 (which is 4) to the other side: x=12-4
Now you get: x = 8