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MP Find the Error A student was finding

the hypotenuse of an isosceles right
triangle. The legs were each 20 millimeters.
Find the mistake and correct it.
(20+20)² = c²
40² = c²
40 = C

User Labeo
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1 Answer

4 votes

Answer:

Explanation:

Okay, let's analyze this step-by-step:

Given:

- Isosceles right triangle

- Legs are each 20 mm

- Trying to find the hypotenuse (c)

Working:

- The legs are each 20 mm

- By Pythagorean theorem: c^2 = a^2 + b^2

- Here a = b = 20 mm

- So c^2 = (20)^2 + (20)^2

- c^2 = 400 + 400

- c^2 = 800

- c = √800

- c = 28.28 mm

Mistake:

- The working incorrectly calculated (20 + 20)^2 = c

- This is wrong, as it squares the sum instead of each leg separately.

Correction:

- Should be c^2 = (20)^2 + (20)^2

- Not (20 + 20)^2

Therefore, the correct hypotenuse length is:

c = √800 = 28.28 mm

User Dunk
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7.7k points