Thread: Application of Quadratics help

1. Application of Quadratic Graphs

The path of a javelin thrown by Marita is given by the formula $\displaystyle h=-\frac{1}{16}(d-10)^2+9$ where h meters is the height of the javelin above ground and d meters is the horizontal distance travelled.

1. What are the possible values of d?
the book says the answer is 0=<d=<22,my question is what is the process of getting those values?

2. Originally Posted by 22upon7
The path of a javelin thrown by Marita is given by the formula $\displaystyle h=-\frac{1}{16}(d-10)^2+9$ where h meters is the height of the javelin above ground and d meters is the horizontal distance travelled.

1. What are the possible values of d?
the book says the answer is 0=<d=<22,my question is what is the process of getting those values?

just graph the function and u ll see...u know that the javelin is thrown at some height above ground where x=0, that is why u ll start with zero...then in order to find where the javelin lands, just put zero for y and solve for x....u ll get 22....therefore the domain would be 0=<d=<22

3. If you solve it you get -1/16 (d-7) (d-13)

D=7 or 13

Then do you have to add them both together to get 20?