Answer: 5 seconds
<u>Step-by-step explanation:</u>
Maximum height is the y-value of the vertex. The number of seconds at maximum height is the x-value (aka axis of symmetry).
h(x) = -2x² + 20x + 48
a=-2 b=20 c=48
Axis of symmetry: x = 
= 
= 
= 5

<em>In decimal form, a = 114.5; b = 25.5</em>
We will write this as a system of equations, where
and
are the two angles.

We will use substitution to solve this system. We know what
equals, so we plug that into the second equation.

Combine the like terms.

Add
on both sides.

Divide both sides by
.

Now just subtract that from
.

I think the wrong is the answer , I hope that help , good luck
Answer:

Interval notation: 
Step-by-step explanation:
<u>First inequality:</u>
<u />
Therefore, this inequality restricts:

<u>Second inequality:</u>

Therefore, this inequality restricts:

Therefore, with both of these restrictions together, we have:
.