A 10-ft ladder rests against a vertical wall

MATHEMATICS · Single correct · AP · Calculus AB · Contextual Applications of Differentiation · Contextual Applications of Differentiation

Problem

A 10-ft ladder rests against a vertical wall. The bottom of the ladder slides away from the wall at 2 ft/s. At what horizontal distance

x

(to the nearest tenth of a foot) is the area of the right triangle formed by the ladder, wall, and ground no longer changing? (a)

10.0\text{ ft}

(b)

7.1\text{ ft}

(c)

5.0\text{ ft}

(d)

8.2\text{ ft}