So, h(t) is how far is Daniel's head from the surface of the water, namely the surface itself is when the height is nill, so his head is at the surface and the height of it is just 0, thus h(t) = 0. Namely, what is "t" when h(t) is 0?

clearly the seconds cannot be a negative unit, so is not -3/2.
Additive identity because that is the property when you add something to 0 and get the same thing
<h3>
Answer: 5 < x < 29</h3>
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Explanation:
Since AB is smaller than AD, this must mean the angle ACB is smaller than angle ACD. Note how these angles are opposite the sides mentioned.
So 2x-10 < 48
At the same time, 2x-10 is also larger than 0.
Overall, we can say 0 < 2x-10 < 48
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Let's solve for x
0 < 2x-10 < 48
0+10 < 2x < 48+10 ...... add 10 to all sides
10 < 2x < 58
10/2 < x < 58/2 ..... divide all sides by 2
5 < x < 29
(-1,-9) because if we substituted 1 into x y would be 9 and if we substituted 1/2 into x y would be 3 but if we substituted -1 into x y would be 1/9 so therefore that value is incorrect