The equation of line q is 5y - 4x = 10. write an equation of the line that is perpendicular to q and passes through the point (-15, 8).

Y=mx+b
m=slope
b=y intercept

perpendicuar lines have slopes that multiply to get -1
so
solving for y
add 4x both sides and divide by5 to get
y=4/5x+2
slope is 4/5

perpendicular means the slopes multiply to get -1
so
4/5 times what=-1?
what=-5/4

so
y=(-5/4)x+b
find b
given the point (-15,8)
8=(-5/4)(-15)+b
8=75/4+b
-43/4=b

y=(-5/4)x-43/4

Maybe the answer is 20mm. all i really did was just multiply, which is obvious.