# maths

posted by jatin

A model rocket is launched with an initial velocity of 250 ft per second. The height h, in feet, of the rocket t seconds after the launch is given by
h = −16t2 + 250t.
How many seconds after the launch will the rocket be 500 ft above the ground? Round to the nearest hundredth of a seconds?

1. Steve

-16t2 + 250t = 500

solve for t

2. jatin

t=2

3. John1

No.

You have to set this equal to zero.

16t^2 -250t + 500 = 0

Now, this isn't factorable. You have to use the quadratic equation to solve for t to the nearest hundredth.

Quadratic x = opposite of b (plus or minus) the square root of( b squared minus 4ac). All of this divided by 2a.

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