x = 10°
ABC = 65°
CBD = 25°
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Both the angles lie inside of right angle triangle whose interior angle sums up to total 90°
Solve for x :
- 4(x) + 25 + x + 15° = 90°
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- ABC = 4(x) + 25 = 4(10) + 25 = 65°
- CBD = x + 15° = 10 + 15° = 25°