How do you solve the system of equations 7x - 2y = - 33 and 5x + 4y = 9 by elimination?

1 Answer
Mar 22, 2017

x=-3
y=6

Explanation:

7x-2y=-33 -----------------------(1)
5x+4y=9 ------------------------(2)

Multiply equation (1) with 2

7x-2y=-33 -----------------------(1) xx 2

14x-4y=-66 ----------------------(3)
5x+4y=9 ------------------------(2) ---(3)+(2)
19x=-57
x=(-57)/19=-3

x=-3

Substitute x=-3 in equation (1)

7(-3)-2y=-33
-21-2y=-33
-2y=-33+21=-12
y=(-12)/(-2)=6
y=6