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35 votes
Please Also Include explanation

Please Also Include explanation-example-1
User Bignose
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2 Answers

14 votes
14 votes
perimeter of the triangle is
9 + 40 + 41 = 90
User Johans
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24 votes
24 votes

Explanation:

since it is a right-angled triangle, the principle of Pythagoras has to be fulfilled :

c² = a² + b²

c being the Hypotenuse (the side opposite of the 90° angle), which is in our case (x + 32).

a and b are the legs.

so

(x + 32)² = x² + (x + 31)²

x² + 64x + 1024 = x² + x² + 62x + 961

2x + 1024 = x² + 961

x² - 2x - 63 = 0

as 63 = 7×9

and -9 + 7 = -2

we can conclude that this quadratic equation is the same as the following factorization :

(x + 7)(x - 9) = 0

we have 2 solutions :

x = -7

x = 9

as x is also the length of a side, the negative solution does not make any sense.

so, x = 9 is our solution.

that means the sides of the triangle are

x = 9

x + 31 = 40

x + 32 = 41

and the perimeter of the triangle is

9 + 40 + 41 = 90

User Lkanab
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2.6k points