Question

Y=-x+1
23 = 5y - 4x
How do I find x and y by using substitution?

Answer 1

final answer x= -2, y=3

Explanation:

y= -x +1 (1)

23=5y-4x --> 5y=4x+23 (2)

Substitute (1) into (2)

5(-x+1)=4x+23

-5x+5=4x+23

-5x-4x=23-5

-9x=18

x=-2

substitute x=2 into (1) y=-(-2)+1, y=3

Answer 2

x = -2 y = 3

Explanation:

Equation 1: y = -x + 1

Equation 2: 23 = 5y -4x

Take and plug in what y equals (from equation 1) into equation 2

23 = 5(-x+1) - 4x

23 = -5x + 5 - 4x

23 = -9x + 5

18 = -9x

x = -2

Then plug the -2 in to the first equation for x

y = -(-2) + 1

y = 2 + 1

y = 3