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Help idk how to do this

Help idk how to do this-example-1
User Meva
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2 Answers

4 votes

Answer:

x = 29

Explanation:

Focus on ΔDEC first. We know that two of its angles are ∠C = 48° and ∠D = 74°.

All of a triangle's angles must add up to 180° by the Triangle Sum Theorem. 48° + 74° = 122°. 180° - 122° is 58°. So ∠E is 58°.

Because the triangles are congruent, ∠E corresponds to ∠B.

Because ∠B is "2x," divide 58° by 2. 58° ÷ 2 = 29°. 29° × 2 = 58°, so this checks out.

I hope this helps!!

User Kayson
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4.8k points
1 vote

Answer: 58°

Explanation:

They say the triangles are equal. And they give us more information for the triangle on the right.

∠E = ∠B

We know ∠C and ∠D, so you should add them all up to equal 180. (degree of a triangle)

74 + 48 + ∠E = 180

122 + ∠E = 180

∠E = 58

So therefore ∠B = 58

User Conradj
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4.3k points