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In △ ABC and △ ACD, ∠ ACB = ∠ ADC = 90 °, AC = 5, ad = 4. When BC is equal to what, △ ABC is similar to △ ADC? Explain your reason Picture: a right triangle on the left is placed upright, with vertex a, bottom left B, bottom right C, ∠ C as right angle, and a right triangle on the right is smaller than △ ABC, one side is collinear with AC, two outer sides are right angles with D, ∠ d. A is also the vertex of the right triangle, and C is another point except vertex and right angle Answer before April 10
Triangles are similar, the big angle is proportional to the big side, and the corresponding side is proportional
AB/AC=AC/AD
So AB = AC * AC / ad
AB=25/4
According to the triangle Pythagorean theorem, in the triangle ABC,
BC=15/4
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