186.
The hypotenuse of a right angled triangle is 6 metres more than twice the shortest side. If the third side is 2 m less than the hypotenuse, find the sides of the triangle.
Let the shortest side of the triangle be x m. Then,
Hypotenuse = (2x + 6) m
and third side = (2x + 6 – 2) m
= (2x + 4) m
According to Pythagoras theorem, we have
(2x + 6)2 = x2 + (2x + 4)2
⇒ 4x2 + 24x + 36 = x2 + 4x2 + 16x + 16
⇒ 24x - 16x + 36 - 16 = x2
⇒ 8x + 20 = x2
⇒ x2 – 8x – 20 = 0
⇒ x2–10x + 2x - 20 = 0
⇒ x(x– 10) + 2(x – 10) = 0
⇒ (x – 10) (x + 2) = 0
⇒ x – 10 = 0 or x + 2 = 0
⇒ x = 10 or x = –2
As length of the side cannot be negative, it is rejected.
∴ 2x + 4 = 20 + 4 = 24 and 2x + 6 = 20 + 6 = 26
Thus, the side of the triangle are 10 m, 24 m and 26 m.
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