4x + 2y = 8
y = mx + b
Subtract 4x from both side
2y = 8 - 4x
Divided each term by 2
y = 4 - 2x
y = -2x + 4
Using the slope-intercept form, the slope is -2
m = -2
The equation of a perpendicular line to y = -2x + 4 must has a slope that is the negative reciprocal of the original slope.
M perpendicular = - 1/-2
Move the negative infront of the fraction
M perpendicular = 1/2