The Point $P ( 16,4 )$ Lies on the Curve $y = \sqrt { x }$

Multiple Choice

The point $P ( 16,4 )$ lies on the curve $y = \sqrt { x }$ . If is the point $Q ( x , \sqrt { x } )$ , use your calculator to find the slope of the secant line $P Q$ (correct to six decimal places) for the value $x = 3.89$ .

A) $m _ { P Q } = - 0.044439$
B) $m _ { P Q } = - 0.167439$
C) $m _ { P Q } = - 0.307439$
D) $m _ { P Q } = 0.377439$
E) $m _ { P Q } = 0.167439$