Question

X+y= 1......... 4x+y = -23
What's x and y

Answer 1

x + y = 1 from this: x = 1 - y

4x + y = -23

Substitute x = 1 - y into the second equation.

4x + y = -23

4*(1 - y) + y = -23

4 - 4y + y = -23

4 + y - 4y = -23

4 - 3y = -23

-3y = -23 - 4

-3y = -27

y = -27/-3

y = 9

Recall: x = 1 - y, substituting y = 9

x = 1 - 9

x = -8

x = -8, y = 9

Answer 2

x + y = 1.....multiply by -1
4x + y = -23
---------------
-x - y = -1 (result of multiplying by -1)
4x + y = -23
---------------add
3x = - 24
x = -24/3
x = -8 <====

x + y = 1
-8 + y = 1
y = 1 + 8
y = 9 <====