+129899 -2.5x+y=13.5
2.25x-y=-12.25
Using the first equation, y = 13.5 + 2.5x....so ....putting this into the second equation, we have......
2.25x - [ 13.5 + 2.5x] = -12.25 simplify
2.25x - 13.5 - 2.5x = -12.25 let's multiply by 100 to clear the decimals
225x - 1350 - 250x = - 1225 add 1350 to both sides, simplify the left side
-25x = 125 divide both sides by -25
x = --5
And using
y = 13.5 + 2.5x → y = 13.5 + 2.5(-5) → y = 13.5 - 12.5 = 1
