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In the triangle ABC on the right, DC = 2bd, CE = 3aE, the area of the shadow is 20 square centimeters, and the area of the triangle ABC is______ Cm
From "DC = 2bd, CE = 3aE", we can get: s △ ade = 14s △ ADC, s △ ADC = 23S △ ABC, s △ ade = 16S △ ABC, so the area of triangle ABC is: 20 △ 16 = 120 (square centimeter), answer: the area of triangle ABC is 120 square centimeter. So the answer is: 120 square centimeter
The area of triangle ABC is 1, extend AB to D, make BD = 2Ab, extend AC to e, make CE = 3aC, find the area of triangle ade
BG: DH = AB: ad = 1:3, i.e. DH = 3bg, so triangle ade area s = 1 / 2 * DH * AE = 1 / 2 * 3bg * 4ac = 12 * (1 / 2 * BG * AC)
The area of triangle ABC is 1, that is, 1 / 2 * BG * AC = 1,
So s = 12 * 1 = 12
In triangle ABC, BD is 2 times of AD, CE is 3 times of AE, and the area of triangle ade is 20 square centimeter
Triangles with the same base and height have the same area
Because: 2ad = BD, CE = 3aE, the shadow area is 20 square centimeters
Area of triangle ABC = 3 s △ ADCs
S △ ADC = 4 s △ ade
So s △ ABC = 3 * 4 * 20 = 240
The area of triangle ABC is 240 square centimeters
As shown in the figure, it is known that ∠ ABC = 40 °, and ∠ bad = ∠ EBC, ad intersects be with F, AD / / eg, he ⊥ be, then the degree of ∠ HEG is_______ .
∠HEG=60°
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