Q8 of 100 Page 17

On a semi-circle with AB as diameter, a point C is taken, so that m(∠CAB)= 30°. Find m(∠ACB) and m(∠ABC).

We have,

∠CAB = 30o


∠ACB = 90o (Angle in semi-circle)


IN triangle ABC, by angle sum property


∠CAB + ∠ACB + ∠ABC = 180o


30o + 90o + ∠ABC = 180o


∠ABC = 60o


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