The Height , H Of A Baksetball , in meters at t seconds after it is tossed out of a window is modeled by : H=-5t^2 + 20t +15. A Boy Shoots At The Baseball With A Paintball Gun . The Trajectory Of The Paintball Is Given By The Equation : H=3t + 3 . Will The Paintball Hit The Baseball ? IF So When? At What Height Will The Baseball bE ? @jtvatsim

- anonymous

- Stacey Warren - Expert brainly.com

Hey! We 've verified this expert answer for you, click below to unlock the details :)

- chestercat

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

- jtvatsim

Alrighty, what have we got here...

- jtvatsim

"something is flying through the air, somebody does something to hit in midair" yep same problem type... :)

- anonymous

Yup Sooo... -5t^2 +20t+15=3t +3

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- jtvatsim

Yessiree! Will the heights be equal? And when? Let's find out. The audience waits in suspense...

- anonymous

Lets Fine Outt Next Step Add ?

- jtvatsim

Either add or subtract, whatever will make the other side 0. Try something, and I'll let you know what I think. :)

- anonymous

Ok Subtract Because there is only one negative .

- jtvatsim

You are right to subtract. But not because there is only one negative. Let's pause on this step to make sure you've got this part down. That way, you'll always have the confidence to get through this stage. :)

- jtvatsim

When I see -5t^2 + 20t + 15 = 3t + 3, I immediately focus my attention on the right side of the equation (look at 3t + 3).

- anonymous

Ok

- jtvatsim

Then, ask yourself, I see a 3t, how can I get rid of it? In this case I could just subtract a 3t from both sides like this:
-5t^2 + 20t + 15 = 3t + 3
-3t -3t
___________________________
-5t^2 + 17t + 15 = 3
Then my 3t is gone!

- jtvatsim

But, then, of course, I still see a pesky 3 there. How could I get rid of that since I just want zero on that side? Well... subtract a 3 from both sides, just like we did before!
-5t^2 + 17t + 15 = 3
-3 -3
--------------------
-5t^2 + 17t + 12 = 0

- anonymous

Ohhh i c

- jtvatsim

Great! It's not too hard once you see the pattern. But it is a little hard to say in words. :)

- jtvatsim

Here's one more example just to make sure you've got it.
-66t^2 + 24t + 31 = -6t + 4
+6t +6t
---------------------------
-66t^2 + 30t + 31 = 4
-4 -4
----------------------
-66t^2 + 30t + 27 = 0

- jtvatsim

In this case, I added to get rid of the -6t, but subtracted to get rid of the +4. Any questions on that process?

- jtvatsim

And of course, what I just wrote above was a made-up example and has nothing to do with "our" current problem. :)

- anonymous

i noticed Lol Those Off #;s

- jtvatsim

Haha! I tried to make it obvious that I was going crazy there. ;) Anyways, we've got our equation now:
-5t^2 + 17t + 12 = 0

- jtvatsim

From what I've seen, that should be the end of the "hard" part mathematically. The rest of the problem is just making sure our calculator does the right thing. :)

- anonymous

Yup
Thats The Last Thing 2 do

- jtvatsim

OK, then. Once you have your proposed solutions from the quadratic formula, we'll compare notes.

- anonymous

Done

- jtvatsim

Awesome! What did you get?

- anonymous

x1=-0.5
x2 :4

- jtvatsim

Yep, that's pretty close to what I got,
x1 = -0.59999
x2 = 4

- anonymous

i got the 9999 2 lol

- anonymous

didnt think i needed it

- jtvatsim

Oh, well, look at you! It's slightly different rounding
-0.59 rounds to -0.6 (then I wouldn't have said anything...)
You can feel that I'm becoming more nit picky! :) That's a good thing, it means you are moving beyond the basics. :)

- anonymous

Lol Im Trying .. Another One Then Ill Leave You Alone Lol

- jtvatsim

No worries! Glad to help. It's fun watching someone start out struggling, but then learn and start mastering it. It's really cool to see happen. :)

- jtvatsim

So, we've got our possible solutions, but we need to check them. Here goes...

- jtvatsim

Looks like t = -0.6 gives h = 1.2
and
t = 4 gives h = 15

- anonymous

The Correct One Is ....4

- jtvatsim

I'd agree, even though the heights are both positive (and therefore possible), the negative time is weird. The answer is Yes, time is 4, and height is 15. Yahoo! :D

- anonymous

Yay !!!!!!!!!! You Helped Me Sooo Much ..After This Next One Ill Have Just Four More ...Wouldve Been Up All Night

- jtvatsim

You are welcome! Based on looking at the problems are they relatively similar? If not, I could help you look at one that is a different type if you feel comfortable with these "objects flying and hitting" questions.

- anonymous

This Next One Is A Different One .

- anonymous

Is a summer packet soo

- jtvatsim

Let's take a look at it then if you want. Even if I have to log off soon, I can at least try to come up with a plan of attack. :)

- anonymous

Sure

- jtvatsim

sounds good

Looking for something else?

Not the answer you are looking for? Search for more explanations.