Q5 of 34 Page 170

If three angles of a triangle are in the ratio 2:3:5, determine three angles.

Let the given angles of a triangle be 2x, 3x and 5x.


We know that the sum of the angles of a triangle is 180°.


⇒ ∠A + ∠B + ∠C = 180°


⇒ 2x + 3x + 5x = 180°


⇒ 10x = 180°


⇒ x = 18°


So, ∠A = 2× 18° = 36°


∠B = 3× 18° = 54°


∠C = 5× 18° = 90°


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