Question

The length of a rectangle is 3 times its width, as shown below.Suppose x = 8If the value of x is increased by 2, what is the perimeter of the newrectangle (Provide the number only. Do not include the unit ofmeasurement.)

Answer 1

Suppose x = 8If the value of x is increased by 2, what is the perimeter of the newrectangle

Answer 2

The perimeter will increase proportional to the value of x. We can write the perimeter in function of x as:

`\begin{gathered} P=2(W+L) \\ P=2(x+3x) \\ P=2\cdot4x \\ P=8x \end{gathered}`

Then, if x=8, the perimeter is:

`P=8\cdot8=64\text{ in}`

If we increase x by 2, we will have x=8+2=10, and the perimeter will be:

`P=8\cdot10=80\text{ in}`

Answer:

For x=8, the perimeter is P=64.

For x=10, the perimeter is P=80 (it is increased by 8*2=16 units)