Question

A rectangle has a length of 4x plus 5 and a width of 8x minus 4. Which expression shows the perimeter of that rectangle? A: 4x + 1 B: 12x - 2 C: 12x + 1 D: 24x + 2

Answer 1

Answer: The answer is (D) $24x+2.$

Step-by-step explanation:  Given that there is a rectangle, where length of the rectangle is given by

$\ell=4x+5,$

and width of the rectangle is given by

$b=8x-4.$

We are to find the perimeter of the rectangle. To do so, we need to add two times length with two times breadth of the rectangle.

Therefore, perimeter is given by

$p=2\ell+2b=2\times(4x+5)+2\times(8x-1)=8x+10+16x-8=24x+2.$

Thus, the correct option is (D).