What is the right answer​

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Explanation:

Angle B = 90 degrees, and the side opposite this is the hypotenuse AC = 10.

Angle C = 30, and the side opposite this smallest angle is AB. For now we'll call this x.

It turns out that for any 30-60-90 triangle, the hypotenuse is twice as long as the short leg. So if x is the short leg, then 2x is the hypotenuse.

Set 2x equal to the given hypotenuse 10 and solve for x

2x = 10

x = 10/2

x = 5

That makes AB = 5.

In other words, we cut the hypotenuse in half to get the length of the shorter leg.

answer is the third choice:

3x^5+4x^4+x^3+2x^2-10x-7=0

step-by-step explanation: