Question

Zohar is using scissors to cut a rectangle with a length of 5x – 2 and a width of 3x + 1 out of a larger piece of paper. Which expression can be used to find the perimeter of the rectangle and what is the perimeter if x = 4?

(5x−2)+(3x+1); 31 centimeters
(5x−2)+(3x+1); 36 centimeters
2(5x−2)+2(3x+1); 62 centimeters
2(5x−2)+2(3x+1); 70 centimeters

Answer 1

Perimeter of a rectangle = 2(length) + 2(width), so expression: 2(5x−2) + 2(3x+1).

If x = 4: length = 5(4)−2 = 18, width = 3(4)+1 = 13, so perimeter = 2(18)+2(13) = 36+26 = 62 cm.

Correct choice: 2(5x−2)+2(3x+1); 62 centimeters.