Question

Solve by Elimination:

4x + 8y = 20
-4x + 2y = 10
(-1,3)
(3,4)
(3,-1)
(4,3)

Answer 1

(-1,3)

Explanation:

Elimination makes solving for the system of equations much easier if it is the faster route. In this case, it is already done for you, and no multiplication is required.

First, we want to eliminate the x values completely because they are opposites and therefore cancel out. Next, you want to add the y-values and sum (20 and 10) so that you get the new equation
`10y=30`. To isolate you need to divide by 10 on each side which will give you
`y=3`.

Now that you have your y-value, you can plug in your value to either of the equations and find what x is. I will use the equation 4x + 8y = 20 to solve for x. We first want to substitute in our y-value so that we get
`4x+8(3)=20` which is simplified to
`4x+24=20` now subtract by 24 on both sides to get 4x by itself to get
`4x=-4`. Lastly, isolate x by dividing by 4 on each side to get
`x=-1`