Question

Parallel Lines find the missing values of x and y equation

This was a level 4+ question I was given on a quiz, and I am going to retake it and want to know how to solve this. I don’t understand at all! Someone please help!

Answer 1

`x=90\\y=-40`

Explanation:

Let's set up a system of equations using the given information.

x+y=50

x-y=130

We can solve this system using elimination. In this case, we can eliminate x by subtracting the two equations.

`x-x+y-(-y)=50-130\\x-x+y+y=50-130`

`2y=-80`

Divide both sides by 2.

`y=-40`

Then, plug -40 in for y to solve for x:

`x+y=50\\x+(-40)=50\\x-40=50\\\text{Add 40 to both sides}\\x=90`

Therefore..

`x=90\\y=-40`