Answer:
Given Perimeter= 70inches.
Lenght=7 less than twice the widthor breadth.
= 2b-7
breadth(or width)=b
Now Permieter of rectangle= 2(l+b) [NOTE: breadtha nd width are same here so we can use with as breth.]
∴2(l+b=)70
⇒2(l+b)=70
We knwow that length=2b-7
⇒2 (2b-7+b)=70
⇒2(2b+b-7)=70
⇒2(3b-7)=70
Opening the bracket...
⇒6b-14=70
Transposing (-14) to the RHS will make it (+14)
⇒6b=70+14
⇒6b=84
Transposing 6 to the RHS...
⇒b=84/6
⇒b=14
Now we have b=14
So we need to find what the lenght is, and as we have the equation L= 2b-7 and now we also know what the value of b is so we can solve the equation to find the lenght.
⇒2b-7= Lenght
⇒2(14)-7=Lenght
⇒28-7=Lenght
⇒21=Lenght
Therfore Lenght is 21 inches and Breadth is 14 inches
