A street light is on top of a 10 foot pole. A
person who is 4 feet tall walks away from the
pole at a rate of 6 feet per second. At what
speed is the length of the person’s shadow
growing?

Question

A street light is on top of a 10 foot pole. A
person who is 4 feet tall walks away from the
pole at a rate of 6 feet per second. At what 
speed is the length of the person’s shadow
growing?

anonymous · Answer

did you learn APs and GPs yet?

anonymous · Answer

no :( I don't know what those are

anonymous · Answer

(y + x)/10 = y/6
6(y + x) = 10y
6y + 6x = 10y
6x = 4y
6(dx/dt) = 4(dy/dt)
(6/4)(3) = dy/dt
18/4 = dy/dt
9/2 ft/s = dy/dt