daughter needs help with math problem!!

Pre-College Topics High School Life
1

<p>D and i are here together, i was on parents forum while D was doing algebra 2. she has a problem an d i am NOT good at math---any help out there??</p>

<p>The heught, H, in feet, aball will reach when thrown in the air is a function of time, t, in seconds, given by the equation</p>

<pre><code> 2
h(t) = -16t + 30t + 6
</code></pre>

<p>Find, to the nearest tenth, the maximum height, in feet, the ball will reach.</p>

<p>This is exactly how the problem reads in her Math B practice for regents book THANKS for any help!!</p>

2

<p>What is the 2 hanging out above the equation?</p>

3

<p>are you sure that it's not -16t^2 + 30t + 6?</p>

4

<p>i'm sorry-- that was supposed to be squared--but i didn't know how to do it!!</p>

5

<p>Use a graphing calculator and set the entire equation equal to Y=. Then use X for "t" and type in the equation. Graph it and use the trace feature to see the highest height that the ball reaches. It should be in the shape of a hill (upside down parabola) with a peak. The peak is the maximum height. :)</p>

6

<p>thank you --i don't understand it but i'm sure D will!!</p>

7

<p>You don't need to use "trace." Hit the "2nd" key and then hit trace to get your calc functions. Then find the maximum of the curve.</p>

8

<p>thanks for such quick responses!!!</p>

9

<p>You're very welcome. Cali is very right. The table works too.</p>

10

<p>can this be done without a graphing calculator??</p>

11

<p>Yes, it can be, but I don't remember my Algebra 2 very well. I <em>could</em> tell you how to do it with calculus, however, but that might not be too helpful.</p>

12

<p>Yes, but it's a pain. You would have to create a table and plug in values for t until you find the highest vaue for H(t). You could start with big numbers and narrow it down but it would take a while.</p>

13

<p>yes</p>

<p>Max x-value=-b/(2a)</p>

<p>h(t) = -16t^2+ 30t + 6
a=-16
b=30</p>

14

<p>Oh good call. -b/2A is the coordinates for the vertex of the parabola which is also the maximum value.</p>

15

<p>thanks so much --she's going to use brothers graphing calculator. she said she got it as soon as she read your answers. THANK YOU to all you great ccers!!</p>

16

<p>You're welcome!!! :)</p>

17

<p>(-b)/(2a) = x value of vertex
now plug that x value into the equation to get the y value of vertex which is the answer</p>