Question

3x-4y=-31
x+y=6
how do you solve this equation out I'm so confused please help

Answer 1

{ 3 x - 4 y = - 31
x + y = 6 * ( - 3 )

3 x - 4 y = - 31
-3x - 3 y = - 18
-----------------------
- 7 y = - 49 * ( -1)

y = 49 / 7

y = 7

For x :

x + y = 6

x + 7 = 6

x = 6 - 7

x = -1

S = { - 1 , 7 }

hope this helps!

Answer 2

3x-4y=-31
-3(x+y)=6

3x-4y=-31
-3x-3y=-18

-7y=-49

y=7

x+y=6
x+7=6
-7 -7

x=-1

x=-1
y=7

(-1,7)