Question

pls answerquestion fasttt

Answer 1

Answer:

r=4

Step-by-step explanation:

area of a =1*3cm2

area of a + b + c= (2+1+1)*(7-r) cm2

area of e =2*1cm2

area of f =1*r cm2

according to question

21=3+4(7-r)+2+r

21=3+28-4r+2+r

21=33-3r

3r=33-21

r=12/3

r=4

therefore r=4cm