Cos( 30 ) = 19√3 / x
√3 / 2 = 19√3 / x
Simplify √3 from both sides
1 / 2 = 19 / x
Multiply both sides by x
1 /2 × x = 19 / x × x
x / 2 = 19
Multiply both sides by 2
x / 2 × 2 = 19 × 2
x = 38
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Sin( 30 ) = y / x
1 / 2 = y / 38
Multiply both sides by 38
38 × 1 / 2 = 38 × y / 38
38 / 2 = y
19 = y
y = 19
Answer:
x = 3
Step-by-step explanation:
49 - 19 = 30
-2x - 12x = 10x
30 / 10 = 3
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°
