Question

Anyone know how to do this?

Answer 1

Answer:
`(10)/(r+5)`

The perimeter of a rectangle is given by the following formula:

`P_(rectangle)=2w+2L` (1)

Where
`w` is the width of the rectangle and
`L` its length.

According to the image:

`w=(2)/(r+5)` (2)

`L=(3)/(r+5)` (3)

So, if we want to find an expression for the perimeter, we have to substitute equations (2) and (3) in (1):

`P_(rectangle)=2((2)/(r+5))+2((3)/(r+5))` (4)

Solving and simplifying:

`P_(rectangle)=(10)/(r+5)` >>>This is the expression

Therefore, the correct answer is option B.