Slope-intercept form: y = mx + b
[m is the slope, b is the y-intercept or the y value when x = 0 ---> (0, y) or the point where the line crosses through the y-axis]
For lines to be perpendicular, their slopes have to be negative reciprocals of each other. [basically changing the sign (+/-) and flipping the fraction/or switching the numerator and the denominator]
For example:
m = 2 or
Perpendicular line's slope =
m =
Perpendicular line's slope = or 4
Since you know the slope of the line is:
y = -3/4x + 5
m =
The perpendicular line's slope is , so plug it into the equation
y = mx + b
To find b, plug in the point (-3, -3) into the equation
-3 = -4 + b Add 4 on both sides to get "b" by itself
1 = b
The y-intercept is 1