A Point on the Graph of Is Moving Along

Multiple Choice

A point on the graph of is moving along the curve in such a way that its x -coordinate is increasing at a rate of 2 units per second. At what rate is the y -coordinate decreasing at the instant the y -coordinate is equal to 10?

A) 40 units per second
B) 20 units per second
C) 5 units per second
D) 4 units per second
E) 50 units per second