# MATH

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I have 12 word problems to do for my class today.
I am not very good at them.
Any suggestions on how to set them up?

they vary from question to question

• MATH -

Turn the word problems into equations, and solve for the unknown quantity or quantities.

Why not give us one or two examples to show you the process?

• MATH -

A model rocket is launched vertically upward from the top of a cliff 144 feet above sea level. This translates to the model y = -16t^2 + 128t + 144 where y is the height in feet and t is the time in seconds after it was launched. After it is launched, when will the rocket hit the water?

• MATH -

It will hit the water when y = 0. You have to solve the quadratic equation.

You can rewrite it (by dividing both sides by -16)
t^2 - 8t - 9 = 0
which factors to
(t-9)(t+1) = 0

Therefore t = 9 seconds is when it hits the ground. The other solution t = -1 second has no meaning

• MATH -

A ball is dropped from a height of 64 feet. It's height above the earth is the feet given by h(t)=-16t^2+64, where t is the number of seconds after it is dropped
a Find h(1)
b how long does it take the ball to fall to the earth