Question

Help please explain how please please, please

Answer 1

split the problem like this.
you were given that each square is 1cm.


so for the rectangle on the left it goes as followed
a= lxw
a= 3 x 5
a= 15

and now do the rectangle on the right
a= lxw
a= 4x2
a= 8

now just add the two together
a= 8+15
a=23cm