Answer:
42=2 ( l + b)
42=2 ( 5+b+b)
42/2= 5+2b
21 = b + 2b
transpose...
2b=21 - 5
2b = 16
2 / 2
b= 8
Step-by-step explanation:
We know that the perimeter of rectangle is 2 (l + w) and let the width be 'b' and let length of rectangular floor be l.
So 42 = 2 ( l + b )
Copy and put 42 = 2 ( 5 + b + b)
Divide 42/2 = 5 + 2b (b+b = 2b and you notice without exponent because we're on addition so you can easily add it)
21= 5 + 2b ( you need to transpose so it will be)
2b = 21 - 5
2b = 16
so 2b/2 = 16/2 ( cancel 2/2 and divide 16/2 and the answer will be 8)
Therefore b=8
