The approximate height, h, in metres, travelled by golf balls hit with two different clubs over a horizontal distance of d metres is given by the following functions:
• seven-iron: h= -0.002d^2 + 0.03d
-nine-iron: h= -0.004d^2 + 0.05d
a. At what distances is the ball at the same height when either of the clubs is used?
b. What is this height?