Math
Solve for 5x - y = - 18 and - x + 4y = 15

Asked by
AnneS2
Last updated by
anonymous
5x - y = - 18
5x - y +y= - 18+y
5x=-18+y
5x+18=-18+y+18
y=5x+18
- x + 4y = 15
- x + 4(5x+18) = 15
- x + 4(5x) (4)(+18) = 15
-x+20x+72=15
19x+72=15
19x+72-72=15-72
19x=-57
19x/19=-57/19
x=-3
y=5x+18
y=5(-3)+18
y=-15+18=3