Question

In the fig., BC = CA and<A = 40°, then find <ACD.
Please answer asap
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Answer 1

Step-by-step explanation:

In ΔABC,

AC=BD....(Given)

∠A=40°...(Given)

Therefore,

∠B=40°....( Isosceles triangle theorem)

Thus,

∠C=100°...(Sum of all angles of a triangle is 180°)

Thus,

∠ACD=80°....(Linear pair of angles)

OR

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You can use remote angle theorem, which states that the sum of two angles of a triangle who are far (remote) from an exterior angle of the triangle is equal to the measure of that exterior angle.