If ABC and DEF are similar triangles such that ∠A = 47° and ∠E = 63°, then the measures of ∠C = 70°. Is it true? Give reason. ∴ Given statement is true. Question 3. Let ∆ABC ~ ∆DEF and their areas be respectively 64 cm 2 and 121 cm 2. If EF = 15.4 cm, find BC. Question 4. ABC is an isosceles triangle right-angled at C. Prove that AB 2 = 2AC 2.
B, D and F are midpoints so DB = 1/2 (AE) BF = 1/2 (CE) DF = 1/2(AC) in this case you only need to find out DF = ? and you also know AC = 50 so DF = 1/2 (AC) DF = 1/2(50) DF = 25 answer DF = 25
