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2 years ago

Which of these choices is the length of the leg of a 45-45-90 triangle with a hypotenuse of 20?

Mathematics

2 answers:

Marta_Voda [28]2 years ago

8 0

Answer: The correct choice is 10√2 units.

Step-by-step explanation: We are given to select the correct choice that gives the length of the leg of a 45-45-90 triangle with a hypotenuse of 20.

Since the given triangle is an isosceles right-angled triangle, so let x units be the length of each of the legs.

Using the Pythagoras theorem, we get

$x^2+x^2=20^2\\\\\Rightarrow 2x^2=400\\\\\Rightarrow x^2=\dfrac{400}{2}\\\\\Rightarrow x^2=200\\\\\Rightarrow x=\pm\sqrt{2\times100}\\\\\Rightarrow x=\pm10\sqrt2.$

Since x is the length of the leg of the given triangle, so we get

x = 10√2 units.

Thus, the correct choice is 10√2 units.

Nuetrik [128]2 years ago

7 0

The answer would be b.20

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Checking all the options one by one:

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