Can someone help me on this

Mathematics

1 answer:

Morgarella [4.7K]3 years ago

4 0

Answer:

m∠A = 91°

Step-by-step explanation:

∠A ≅ ∠B (Vertical Angle Theorem). This means that the two angles will have the same measurements.

Note that a straight line = 180° (Definition of a Straight Line).

Find the value of m∠B.

180 - 47 - 42 = m∠B

m∠B = 180 - (89)

m∠B = 91°

Remember that ∠B & ∠A are vertical angles, so they will have the same measurement.

m∠A = 91°

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