From a platform, an object is projected vertically into the air. Its height, metres above ground level after seconds, is modelled by the equation:

At what height above the ground is the platform from which the object was projected?

4 answers

The equation is h= 3+20t-5t
Pls help me understand
at t = 0, the object is starting to be projected

plug in zero for t in the height equation to find the platform height
That equation is incorrect, should be
h= 3+20t-5t^2 , where t is in seconds, and h is in metres

The steps suggested by R_scott are correct