Question

2x+2y=120 2x +4y = 180 by sustitution method solution​

Answer 1

2x + 2y = 120. (1)

2x + 4y = 180. (2)

___________

multiplying 2 on equation 1 and 1 on equation 2

4x + 4y = 480

2x + 4y = 180

-. -. -

___________

2x = 300

X. = 150

putting X value in equation 1

2*150 +2y = 120

300 + 2y = 120

2y = 120 -300

2y = -180

y= - 90