You are correct. The function should be
h(t) = 25t - 5t^2
The -5t^2 term is due to the downward pull of gravity. The +25t indicates an initial upward velocity.
The question says h= -5t^2-25t models a football being kicked in to the air. And asks for the roots. I found that the roots are -5 and 0. But the answer is 5 and 0. I know time can't be negative. But u can't just switch -5 to 5. Can you.?
2 answers
Parabola - 5 t ^ 2 - 25 t is concave downward.
That's why you get negative time.
You can switch - 5 to 5.
If you want to see graph go on:
w o l f r a m a l p h a . c o m
When page be open in rectangle type:
- 5 t ^ 2 - 25 t , t = 0 to - 5
and click option: =
You wil see graph
That's why you get negative time.
You can switch - 5 to 5.
If you want to see graph go on:
w o l f r a m a l p h a . c o m
When page be open in rectangle type:
- 5 t ^ 2 - 25 t , t = 0 to - 5
and click option: =
You wil see graph