# Math Help - HS Algebra 2-Quadratics, word problem.

1. ## HS Algebra 2-Quadratics, word problem.

I'm taking Algebra 2, this is from the quadratics section. I'm not asking you to do my homework, but please, tell me how. I really appreciate the help. Here's the question:

In an engineering test, a rocket sled is propelled into a target. The sled’s distance d in meters from the target is given by the formula d=-1.5t^2+120 where t is the number of seconds after rocket ignition. How many seconds have passed since rocket ignition when the sled is 10 meters from the target?

I think most of my issue is that I don't quite know what to do with the 10, but I'm not sure.

Thank you for taking the time to read my post.

2. This question didn't come with a formula attached by any chance, did it? Without one, I don't think we have quite enough information to answer the question.

3. Originally Posted by dazygrl02
I'm taking Algebra 2, this is from the quadratics section. I'm not asking you to do my homework, but please, tell me how. I really appreciate the help. Here's the question:

In an engineering test, a rocket sled is propelled into a target. The sled’s distance d in meters from the target is given by the formula where t is the number of seconds after rocket ignition. How many seconds have passed since rocket ignition when the sled is 10 meters from the target?

I think most of my issue is that I don't quite know what to do with the 10, but I'm not sure.

Thank you for taking the time to read my post.
You have a quadratic in $t$ for the distance $d(t)$ travelled in $t$ seconds. You are asked to find the $t$ corresponding to $d(t)=10$. That is you are being asked to solve the quadratic $d(t)=10$. This will have two solutions, you want the positive one.

CB

4. I typed the question wrong, thanks anyway though.