Question

Solve this system of equations by

using the elimination method.
x - 5y = 16
4x - 2y = -8
( , )

Answer 1

`x = - 4`

`y = - 4`

Explanation:

Looking at these equations, we can see neither x or y have the same coefficient. Therefore, we need to multiply or divide, to make either the x or the y the same. It's less of a hassle to make the Xs the same, so let's do that. Taking the top equation and multiplying it by 4, we get:

`4x - 20y = 64`

Now let's subtract the top equation from the bottom equation, leaving us with a third equation:

`- 18y = 72`

Divide 72 by -18 to get

`y = - 4`

Now let's substitute into our first equation to find X:

`x + 20 = 16`

Leaving us with:

`x = - 4`

Now let's substitute into the second equation to check our solution is correct:

`- 16 + 8 = - 8`

This is correct, so the answer is X and Y are both equal to -4