Question

I want first part explained answer
please tell me the correct answer​

Answer 1

Answer:

1.

using Pythagoras therom

BC² = [3.5]² - [2.1]²

BC = ²√7.84

BC = 2.8 cm

PR² = [4.5]²-[3.5]²

PR² = 8

PR = ²√8

PR = 2√2 cm

2.

AB² = [5]²-[3]²

AB² = 16

AB =   ²√16

AB = 4cm

RQ² = [5]²-[4]²

RQ² = 9

RQ = ²√9

RQ = 3cm