Question

The figure shows ∠ABD is 90°, split by line BC. The measure of ∠ABC is x° and the measure of ∠DBC is (3x + 10)°. What is the value of x? Enter your answer in the box.

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Answer 1

From the picture,

∠ABC + ∠DBC = ∠ABD

Substituting with data,

x + (3x + 10) = 90

4x + 10 = 90

4x = 90 - 10

4x = 80

x = 80/4

x = 20

Explanation: