Answer:
![y = \boldsymbol{-(4)/(25)}(x - \boldsymbol{5})^2 + 4](https://img.qammunity.org/2023/formulas/mathematics/college/zzkm770p5k9pnml519369l2u87jsnvz6cl.png)
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Step-by-step explanation:
The instructions don't mention it, but I'm assuming that the height of 4 feet is the max height the of the ball.
If so, then this is the vertex of the parabola.
The ball is on the ground when x = 0 and x = 10. The x coordinate of the vertex is the midpoint of those two roots. So it's at x = 5.
Overall, the vertex is (h,k) = (5,4)
The equation
y = a(x-h)^2 + k
becomes
y = a(x-5)^2 + 4
Next, we plug in the root (x,y) = (10,0) since the ball hits the ground when x = 10. Let's solve for 'a'
y = a(x-5)^2 + 4
0 = a(10-5)^2 + 4
0 = 25a + 4
25a = -4
a = -4/25
We could have used (x,y) = (0,0) and we'd end up with the same 'a' value.
Therefore, the height function is
![y = \boldsymbol{-(4)/(25)}(x - \boldsymbol{5})^2 + 4](https://img.qammunity.org/2023/formulas/mathematics/college/zzkm770p5k9pnml519369l2u87jsnvz6cl.png)