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The shorter leg of a right triangle is 9cm shorter than the longer leg. The hypotenuse is 9cm longer than the longer leg. Find the side lengths of the triangle.Length of the shorter leg: _ cmLength of the longer leg:__ cmLength of hypotenuse __ cm

User Kaniyan
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1 Answer

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Step-by-step explanation:

let the longer leg = x

The shorter leg = 9cm shorter than the longer leg

The shorter leg = x - 9

hypotenuse = 9cm longer than the longer leg

hypotenuse = x + 9

Using pythagoras theorem:

hypotenuse² = shorter leg² + longer leg²

(x + 9)² = x² + (x - 9)²

Expanding:

x² + 9x + 9x + 81 = x² + x ² - 9x -9x + 81

x² + 18x + 81 = 2x² -18x + 81

collect like terms:

18x + 18x + 81 - 81 = 2x² - x²

36x + 0 = x²

x² - 36x = 0

x(x - 36) = 0

x = 0 or (x - 36) = 0

x = 0 or x = 36

if x = 0

shorter side = x - 9 = 0 - 9 = -9

Since the length cannot be negative, x = 36

The longer leg = x = 36 cm

The shorter leg = x - 9 = 36 - 9

The shorter leg = 27cm

The hypotenuse = x + 9 = 36 + 9

The hypotenuse = 45 cm

User YYY
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