Question

The function \[f(x) = -x^2 - 7x + 30\] shows the relationship between the vertical distance of a diver from a pool's surface f(x), in feet, and the horizontal distance x, in feet, of a diver from the diving board. What is a zero of f(x), and what does it represent?

x = 10; the diver hits the water 10 feet away horizontally from the board.

x = 3; the diver hits the water 3 feet away horizontally from the board.

x = 10; the diver jumps in the pool at 10 feet per second.

x = 3; the diver jumps in the pool at 3 feet per second.

Answer 1

I just found the zeroes, I think it was asking for those in the question
-10, 3 If I did my math right cx

Answer 2

please solve your quadratic equation, using the subsequent formula for finding the zeroes:
\[x=\frac{ -b \pm \sqrt{b ^{2}-4ac} }{ 2a }\]
if the equation is:
\[ax ^{2}+bx+c=0\]

Answer 3

you are correct ;)

Answer 4

Do you want me to show my work, orrr...

Answer 5

solving for zeroes,
0=-x^2-7x+30
0=-(x+10)(x-3)
x=-10,3 using the zero product theorum

Answer 6

I think that only x=3 is acceptable, since the situation described in your problem is:

Answer 7

x cant be -10 in the problem because negative distance isnt possible

Answer 8

Yes, that's what I thought too. Due to the scenario it couldn't be negative, and none of the options contain -10 either. cx

Answer 9

So if x = 3, and x is the horizontal distance, in feet, of the distance of the diver from the diving board, then the horizontal distance is 3?

Answer 10

ya

Answer 11

Oh ok, thanks both of you c:
I wish I could give you both a medal, both of your responses were the best c:

Answer 12

thank you! @camerondoherty

Answer 13

No, Thank You! c:

Answer 14

no problem :)

Answer 15

I give medal @acxbox22

Answer 16

thanks

Answer 17

you deserve it!

Answer 18

b? @acxbox22

Answer 19

? 1 month later??

Answer 20

yeah i'm just now getting to this problem :/

Answer 21

oh ya it is b from the work above

Answer 22

Okay got it!!! @acxbox22

Answer 23

yep ;)

Answer 24

thanks! @acxbox22 :)

Answer 25

it is a 2 in 1 problem :)

Answer 26

hahah yeah xD