A perpendicular line has an opposite reciprocal slope. This means that the new line will have a slope of -4/3x. Plug in x and y into the equation y=Mx +b where m is the slope (-4/3): -3=(-3/4)(-3) + b and isolate b: b-3=(-3/4)(-3) b=(-3/4)(-3) +3 b=9/4+3 b=21/4
The final equation is y= -4/3x + 21/4 The y intercept is (21/4).