The body thrown upwards, after 1 s, was at a height of 25m. It is known that the height that a body reaches is calculated

The body thrown upwards, after 1 s, was at a height of 25m. It is known that the height that a body reaches is calculated by the formula h = v0t-5t ^ 2, where v0 is the initial velocity (in m / s), t is the time (in seconds). Determine at what point in time the body will be at a height of 45m.

We substitute h = 25 and t = 1 into the equation of motion and express v0:
v0 * 1- 5 * 1 ^ 2 = 25
v0 = 25-5 = 20 m / s.
Substituting h = 45 into the equation of motion again, we calculate the time corresponding to this height:
25t-5 * t ^ 2 = 45
t ^ 2-5t + 9 = 0
t12 = (5 + -√25-36) / 2
So the equation has no real solutions, the conclusion: the body will never reach a given height.