Question

PLEASE I NEED HELP I DONT UNDERSTAND HOW TO DO ILL GIVW MORE IF RIGHT

Answer 1

Answer: Choice D

$\frac{9\sqrt{2}}{2}$

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Explanation:

We have a 45-45-90 triangle. If x is the leg length, then y = x*sqrt(2) is the hypotenuse.

Solving for y gets us $x= \frac{y}{\sqrt{2}} = \frac{y\sqrt{2}}{2}$

In this case, y = 9 is the hypotenuse which then leads to choice D.

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Another way to find the answer is to use the pythagorean theorem

a = x and b = x are the two congruent legs

c = 9 is the hypotenuse

Solving a^2+b^2 = c^2, aka x^2+x^2 = 9^2, will lead to $x = \frac{9\sqrt{2}}{2}$