Solve by the substituion method, 9x+2y=-44 and -7x+y=47?

9x + 2y = - 44 ............. (1)
- 7x + y = 47 --> y = 7x + 47 ........... (2)

Put eq (2) in eq (1)

9x + 2 (7x + 47) = - 44
9x + 14x + 94 = - 44
23x = - 44 - 94
23x = - 138
x = - 138/23
x = - 6

Put x = - 6 in eq (2)
y = 7x + 47
y = 7 (- 6) + 47
y = - 42 + 47
y = 5

9x + 2(47 + 7x) = - 44
23 x = - 44 - 94
23 x = - 138
x = - 6

42 + y = 47
y = 5

x = - 6 , y = 5

9x + 2y = -44
-7x + y = 47

-7x + y = 47
y = 7x + 47

9x + 2y = -44
9x + 2(7x + 47) = -44
9x + 14x + 94 = -44
23x = -44 - 94
23x = -138
x = -138/23
x = -6

7x + y = 47
7(-6) + y = 47
-42 + y = 47
y = 47 + 42
y = 89

∴ x = -6 , y = 89

You can rearrange the second equation into y = 7x + 47

Now plug that into the first equation and solve for x

9x + 2(7x + 47) = -44
9x + 14x + 94 = -44
23x = -138
x = -138/23 = -6

Now that we know what x is, plug that into either equation to solve for y

9(-6) + 2y = -44
2y = 10
y = 5

ANSWER -------> x = -6, y = 5