Answer:
DA = 285.7 m
Step-by-step explanation:
First we need to find the side AB in the triangle ABC, and we can do this using Pythagoras' theorem:
AB^2 = BC^2 + AC^2
AB^2 = 300^2 + 400^2
AB^2 = 25000
AB = 500 m
We can find the angle ABC with the tangent relation:
tangent(ABC) = 400/300 = 4/3
ABC = 53.13°
From triangle ABC, we have:
ABC + BCA + CAB = 180°
53.13 + 90 + CAB = 180
CAB = 36.87°
From triangle DAC, we have:
DAC + ACD + CDA = 180
36.87 + 45 + CDA = 180
CDA = 98.13°
Now to find the side of DA, we can use law of sines in triangle DAC:
DA/sin(DCA) = AC/sin(CDA)
DA/sin(45) = 400/sin(98.13)
DA = 400 * 0.7071 / 0.9899 = 285.7258 m
Rounding to nearest tenth, we have DA = 285.7 m
Answer:
ten thousands
Step-by-step explanation:
Since 40%=40/100=4/10, we can divide 11 by 10 and multiply that by 4 to get the weight gained, which is 1.1*4=4.4. The weight gained paired with the starting weight = 10+4.4=14.4
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°