Help pl differentiation

Two cyclists 84 miles apart start riding toward each other at the samen time. one cycles 2 times as fast as the other. if they meet 4 hours later what is the speed (in miles) of the faster cyclists

The table represents a function f(x). what is f(3)? a.-9 b.-1 c.1 d.9

Given: klmn is a parallelogram m? n=3m? k, lf ? kn , ld ? nm kf=2 cm, fn=4 cm find: lf, ld