HELPPPP ME PLZZZZ!!!!!!

14. Each leg is [tex]21\sqrt{2}[/tex] units long.
15 (a). The longer leg is [tex]7\sqrt{3}[/tex] units long
15 (b). The hypotenuse is [tex]14[/tex] units long
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Explanations:
For a 45 degree right triangle, aka 45-45-90 triangle, the hypotenuse is equal to sqrt(2) times the short leg. Algebraically we can say
[tex]y = x\sqrt{2}[/tex] where x is the leg and y is the hypotenuse
Let's solve for x
[tex]y = x\sqrt{2}\\\\x\sqrt{2} = y\\\\x = \frac{y}{\sqrt{2}}\\\\x = \frac{y\sqrt{2}}{\sqrt{2}*\sqrt{2}} \ \text{rationalizing denominator}\\\\x = \frac{y\sqrt{2}}{2}\\\\[/tex]
Now plug in the given hypotenuse y = 42, this leads to,
[tex]x = \frac{y\sqrt{2}}{2}\\\\x = \frac{42\sqrt{2}}{2}\\\\x = \frac{42}{2}\sqrt{2}\\\\x = 21\sqrt{2}\\\\[/tex]
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For a 30-60-90 triangle, the hypotenuse is double that of the short leg. So the hypotenuse is 2*7 = 14.
The longer leg is equal to sqrt(3) times the short leg. The longer leg is [tex]7\sqrt{3}[/tex]