A 25 ft ladder is leaning against a vertical wall. The bottom of the ladder is pulled horizontally away from the wall at 3 ft/sec. Determine how fast the top of the ladder is sliding when the bottom of the ladder is 15 ft from the wall

Question

A  25 ft ladder is leaning against a vertical wall.  The bottom of the ladder is pulled horizontally away from the wall at 3 ft/sec. Determine how fast the top of the ladder is sliding when the bottom of the ladder is 15 ft from the wall <----- PLEASE EXPLAIN STEPS!

anonymous · Answer

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$$y=\sqrt{625-x ^{2}}$$

$$dy/dt = (1/2)(-2x)/\sqrt{625-x ^{2}}(dx/dt)$$

so at dx/dt =3 and x=15

dy/dt= -3/4 ft/s

negative sign shows ladder is sliding downwards

anonymous · Answer

sorry multyply 3 also i forget to multiply 3...its -9/4 ft/s