Question

plzz solve question number 12 in the following image

Answer 1

If you consider the ΔEDC,
By applying Pythagoras Theorem,

ED² = EC² + CD²
ED² = (2.4)² + (1.8)²
ED² = 5.76 + 3.24
ED² = 9.00
ED = √9 = 3

So, ED = 3 cm

Now, BF = CD
BF = 1.8 cm

Now consider the ΔABE,
AB = AF + BF = 1.8 cm + 1.2 cm = 3 cm
By applying Pythagoras Theorem,
AE² = AB² + BE²
AE² = (3)² + (√7)²
AE² = 9 + 7
AE = √16 = 4 cm

So,AE = 4 cm

We got AE = 4 cm , ED = 3 cm and AD = 5cm
AE² + ED² = (4)² + (3)² = 16 + 9 = 25 cm
AD² = (5)² = 25 cm

Therefore,
AE² + ED² = AD²

So measure of ∠AED = 90°
As the triangle follows pythagoras theorem.

Hope This Helps you!