what are the zeros of the function h(t)=-5t^2 + 20t

Question

The height of a crab h(t), in metres, dropped by a seagull to the rocks below is given by the function h(t)=-5t^2 + 20t, where t is the time in seconds, after it is released. What are the zeros of the function?

Answer 1

h(t)=-5t² + 20t = 0

 

-5t(t-4) = 0

 

t=0, t=4