Answer:
x = 28⁰
Explanation:
sum of the angles of a triangle = 180⁰
∠A + ∠B + ∠C = 180⁰
∠A = 5x - 60⁰
∠B = 2x + 40⁰
∠C = 3x - 80⁰
:- Solution
∠A + ∠B + ∠C = 180⁰
5x - 60 + 2x + 40 + 3x - 80 = 180⁰
5x + 2x + 3x - 60 + 40 - 80 = 180⁰
10x - 20 - 80 = 180⁰
10x - 100 = 180⁰
10x = 180 + 100⁰
10x = 280⁰
x = 280⁰/10
x = 28
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