Answer:
7. ∠CBD = 100°
8. ∠CBD = ∠BCE = 100°; ∠CED = ∠BDE = 80°
Step-by-step explanation:
7. We presume the angles at A are congruent, so that each is 180°/9 = 20°.
Then the congruent base angles of isosceles triangle ABC will be ...
∠B = ∠C = (180° -20°)/2 = 80°
The angle of interest, ∠CBD is the supplement of ∠ABC, so is ...
∠CBD = 180° -80°
∠CBD = 100°
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8. In the isosceles trapezoid, base angles are congruent, and angles on the same end are supplementary:
∠CBD = ∠BCE = 100°
∠CED = ∠BDE = 80°
i can't really see the image but i'm sure it's pretty cool (:
Answer:
Trigonometry can be used to measure the height of a building or mountains
Step-by-step explanation:
if you know the distance from where you observe the building and the angle of elevation you can easily find the height of the building. Similarly, if you have the value of one side and the angle of depression from the top of the building you can find and another side in the triangle, all you need to know is one side and angle of the triangle.