How do you solve the following system: 4x + y = -1 , 5x - 7y = 12 4x+y=1,5x7y=12?

1 Answer
Apr 13, 2018

x=5/33x=533
y=-5/3y=53
(5/33, -5/3)(533,53)

Explanation:

4x+y=-14x+y=1, 5x-7y=125x7y=12
Take the first equation, 4x+y=-14x+y=1, and isolate yy:
y=-4x-1y=4x1. We can substitute this value into the second equation:
5x-7(-4x-1)=125x7(4x1)=12. Distribute the parentheses:
5x+28x+7=125x+28x+7=12 Combine like terms, isolate xx and coeffecient:
33x=533x=5 Isolate xx:
x=5/33x=533 Input this value into the first equation:
4(5/33)+y=-14(533)+y=1 Distribute yy
20/33+y=-12033+y=1 Isolate yy
y=-55/33y=5533
y=-5/3y=53