Re: In the figure above, the triangle ABC is inscribed in the circle; the
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27 Sep 2023, 09:08
Let the length of the sides BC, AC and AB, respectively be 3x, 4x and 5x, where x is a constant of proportionality.
We see that: (5x)^2 = (3x^2) + (4x)^2 => Triangle ABC is right-angled at C.
=> AB is the diameter of the circle (since the diameter subtends 90° at the circumference)
Sum of the three sides of the triangle = 3x + 4x + 5x = 12x.
Since the perimeter of the triangle is 48, we have 12x = 48 = > x = 4 = > Diameter of the circle = AB = 5x = 20
= > Radius of the circle 20 /2 = 10
=> Circumference of the circle \(= 2.7 \pi \times 10 = 20 \pi\)