Question

1. if both the length and width of a rectangle are doubled, then the perimeter will be —

doubled.
multiplied by 4.
increased by 4 units.
increased by 2 units.

Explanation:

Step1: Recall perimeter formula

The perimeter formula of a rectangle is $P = 2(l + w)$, where $l$ is the length and $w$ is the width.

Step2: Find new - length and new - width

If the length and width are doubled, the new length is $l_{new}=2l$ and the new width is $w_{new}=2w$.

Step3: Calculate new perimeter

The new perimeter $P_{new}=2(l_{new}+w_{new})=2(2l + 2w)=2\times2(l + w)=4(l + w)$.
The original perimeter is $P = 2(l + w)$, and the new perimeter $P_{new}$ is $2P$. So the perimeter is doubled.

Answer:

doubled.