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H(x) = -(x + 1)(x - 7)
What is the maximum height that the ball will reach?

User Xcer
by
5.6k points

2 Answers

4 votes

Answer:

16

Explanation:

All we have to do is write this in vertex form of a quadratic. It is now in factored form. To get it into vertex form we must complete various steps. Here you can skip it using desmos graphing calculator:

H(x) = -(x + 1)(x - 7) What is the maximum height that the ball will reach?-example-1
User Richard Peterson
by
4.9k points
3 votes

Answer: 16 units.

Explanation:

To find the vertex, first simplify the quadratic equation into its standard form:


h(x)=-(x+1)(x-7)\\h(x)=(-x-1)(x-7)\\h(x)=-x^2+6x+7\\

Using this formula, we can then find the axis of symmetry by using the formula S = -b/2a:


S=(-6)/(-2)

The axis of symmetry lies on x = 3.

You can then substitute x for 3 in the equation to find the vertex of the parabola:


h(3)=-9+18+7\\h(3)=16

The ball will be 16 units high after travelling 3 units horizontally. This is the maximum height the ball will reach before falling.

User Cheliyan
by
5.8k points