y = 3/5x - 1....slope here is 3/5. A perpendicular line will have a negative reciprocal slope. All that means is flip the slope and change the sign. So the slope we need is -5/3.
y = mx + b
slope(m) = -5/3
(-9,4)...x = -9 and y = 4
now we sub and find b, the y int
4 = -5/3(-9) + b
4 = 15 + b
4 - 15 = b
- 11 = b
so ur perpendicular line is : y = -5/3x - 11
