A 13 foot ladder is leaning against a wall. If the top slips down the wall at a rate of 2 ft/s, how fast will the foot be moving away from the wall when the top is 8 feet above the ground?
The foot will be moving at ....ft/s.
The foot will be moving at ....ft/s.
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Sahara -
Answer is 1.56 ft / sec
Main equation: a^2 + b^2 = 13^2 , where a is height above ground and b is distance from wall.
Implicit differentiation: 2aa' + 2bb' = 0 , now plug in a = 8 and a' = - 2 and solve for b = sqrt 105 using Pythagorean.
Now simply solve for b' = 1.56
Hope that helps
Answer is 1.56 ft / sec
Main equation: a^2 + b^2 = 13^2 , where a is height above ground and b is distance from wall.
Implicit differentiation: 2aa' + 2bb' = 0 , now plug in a = 8 and a' = - 2 and solve for b = sqrt 105 using Pythagorean.
Now simply solve for b' = 1.56
Hope that helps