Q11 of 57 Page 63

In figure, if ∠D = ∠C, then it is true that ∆ADE ∼ ∆ACB? Why?

(True)

In ∆ADE and ∆ACB,


Given,


∠D = ∠C


∠A = ∠A [common angle]


As we know sum of all the angles of a triangle is equals to 180∘.


So, by angle sum property of triangle the third angle of both triangles must be equal.


∠E = ∠B


∴ ∆ADE ∼ ∆ACB [by AAA similarity criterion]


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