Question

Equation solutions help...please explain :(

Noelle stands at the edge of a cliff and drops a rock. The height of the rock, in meters, is given by the function f(x) = –4.9x2 + 17, where x is the number of seconds after Noelle releases her rock.

Cesar, who is standing nearby on the ground, throws a rock straight up in the air. The height of Cesar’s rock, in meters, is given by the function g(x) = –4.9x2 + 13x, where x is the number of seconds after he releases his rock.

There is a moment when the rocks are at the same height. What is this height? Round your answer to the nearest tenth of a meter.