Answer:
4x +3y = 10
Step-by-step explanation:
The radius CD has slope Δy/Δx = (1-(-2))/(8-4) = 3/4.
The equation for the perpendicular line through point C(4, -2) can be written as ...
Δx(x -4) +Δy(y -(-2)) = 0
4(x -4) +3(y +2) = 0
4x +3y -10 = 0 . . . . . . general form equation for the line
4x +3y = 10 . . . . . . . . .standard form equation for the line
So...the diameter is increasing at a rate if 2cm/minute, therefore the radius (1/2 the diameter) is increasing at half the rate. You will learn how to calculate the rate of change at a specific point in time in calculus.