Question

When WIll This Rocket Hit the Ground

y = -5t^2+23t+10

Is 5.4 seconds the correct answer?

Answer 1

The factored form is
h=−(5t+2)(t−5)

Answer 2

So we subtract the two x-intercepts right, giving 5.4 but the answers in the textbook say 5 seconds so I am confused

Answer 3

Rocket hit the ground when y = 0 so 0 = (5t+2)(t−5)

Answer 4

Yea, well I get 5.4 by doing that

Answer 5

it doesn't factor that way

Answer 6

How did you get 5.4? because I get 5.

Answer 7

i get neither

Answer 8

How did you guys factor it?

Answer 9

\[-5t^2+25t+10=0\] divide by \(-5\) get
\[t^2-5t-2=0\] the use the quadratic formula

Answer 10

satellite's right, (5t+2)(t−5) is not correct

Answer 11

-5(5.372281323269014)^2+25(5.372281323269014)+10=0

Answer 12

We have yet to learn the quadeatic formula, we do this by factoring and looking at the x intercepts

Answer 13

Factor -5 out.
-5t^2+25t+10 = -5(t^2 - 5t - 2)

Answer 14

then either there is a typo, or you have to guess at the solution, because this one does not factor over the integers

Answer 15

There is a tyop it was actullt 23t

Answer 16

imagine...

Answer 17

\[-5t^2+23t+10=0\] or
\[5t^2-23t-10=0\]now factor
\[(t-5)(5t+2)=0\] so \(t=5\) or \(t=-\frac{2}{5}\)

Answer 18

pick \(t=5\) because you are not going backwards in time

Answer 19

@satellite73 say, both the x-intercepts were positive, the what would we doo

Answer 20

For an example, what if the two x-intercepts were positive like 5 and 1

Answer 21

if you have two positive intercepts , then when t= the first intercept, the rock will be coming out of the ground and landing when t = the latter intercept ,