Question

Use substitution to solve the system of equations.
3 - 5y = 36
22 + y = -16

Answer 1

(-4, -8)

Explanation:

x - 5y = 36; 2x + y = -16

first, rearrange the first equation by adding 5y to both sides to isolate x

x = 5y + 36

then plug that in for x in the second equation and solve for y:

2(5y +36) + y = -16 distribute 2 to (5y + 36)

10y + 72 + y = -16 combine like terms by adding 10y and y

11y + 72 = -16 subtract 72 from both sides

11y = -88 divide both sides by 11

y = -8

next, plug y in and solve for x

x - 5(-8) = 36

x + 40 = 36 subtract 40 from both sides

x = -4

finally, check the solution by plugging x and y into both equations to see if they equal the expected value

(-4) - 5(-8) = -1 + 40 = 36 = 36 ✓

2(-4) + (-8) = -8 -8 = -16 = -16 ✓