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Need the measure of angle ABC please

Need the measure of angle ABC please-example-1

1 Answer

6 votes

Answer:

∠ ABC = 38°

Explanation:

given AB = DB then Δ ABD is isosceles with base angles congruent, that is

∠ BDA = ∠ BAD = 71°

the sum of the 3 angles in Δ ABD = 180° , so

∠ ABC + 71° + 71° = 180°

∠ ABC + 142° = 180° ( subtract 142° from both sides )

∠ ABC = 38°

User Sebastian Ax
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