Y= 2x + 4
Substitute y=0
0= 2x + 4
Move variable to the left-hand side and change its sign
-2x=4
Divide both sides of the equation by -2
Answer: X = -2
Y=4x - 8
substitute y = 0
0= 4x - 8
Move variable to the left-hand side and change its sign
-4x = -8
Divide both sides of the equation by -4
Answer: x = -2
