Question

It is the revision worksheet of my school plz solve it if you are expert and don't reply if you don't know ​

Answer 1

Answer:-

384 cm²

Explanation:-

Area of the shaded region:-

=> Area of ∆ABC - Area of ∆ADB

Firstly, let's calculate the area of ∆ADB:-

= 1/2×base×height

= 1/2×12×16

= 96cm²

Hence, area of ∆ADB is 96cm².

In ∆ADB:-

According to Pythagoras theorem:-

=> AB² = AD²+BD²

=> AB² = (12)²+(16)²

=> AB² = 400

=> AB = √400

=> AB = 20cm

Now, in ∆ABC:-

Let a = 52cm; b = 48cm; c = 20cm

Semiperimeter of ∆ABC (s) = a+b+c/2

= 52+48+20/2

= 60cm

Now, according to Heron's formula, area of ∆ABC, will be:-

= √s(s-a)(s-b)(s-c)

= √60(60-52)(60-48)(60-20)

= √60×8×12×40

= √480×480

= 480cm²

Hence, area of ∆ABC is 480cm².

Area of the shaded region:-

= (480-96) cm²

= 384 cm²

Thus, area of the shaded region

is 384cm².

Answer 2

Answer:

345 is the correct answer.