Pythagorean theorem:
( x + 3 )² + ( x + 1 )² = ( 2 x )²
x² + 2 ∙ x ∙ 3 + 3² + x² + 2 ∙ x ∙ 1 + 1² = 4 x²
x² + 6 x + 9 + x² + 2 x + 1 = 4 x²
2 x² + 8 x + 10 = 4 x²
Subtract 4 x² to both sides
2 x² + 8 x + 10 - 4 x² = 4 x² - 4 x²
- 2 x² + 8 x + 10 = 0
Divide both sides by - 2
x² - 4 x - 5 = 0
The solutions are x = 5 and x = - 1
Length cannot be negative so x = 5
Proof:
( x + 3 )² + ( x + 1 )² = ( 2 x )²
( 5 + 3 )² + ( 5 + 1 )² = ( 2 ∙ 5 )²
8² + 6² = 10²
64 + 36 = 100
100 = 100
if three sides of a right angled triangle is given by (x+3)cm,(x+1)cm and 2xcm as the hypotenuse find the value of x
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