Question

Y=x+5
4x+y=20
Solving system by substitution

Answer 1

y = x + 5....so we sub in x + 5 for y in the other equation

4x + y = 20
4x + x + 5 = 20
5x + 5 = 20
5x = 20 - 5
5x = 15
x = 15/5
x = 3

y = x + 5
y = 3 + 5
y = 8

solution is (3,8)