The length of a rectangle is five times its width. if the area of the rectangle is 84m, find its perimeter.

The width of the rectangle can be represented as x, and the length can be 5x.  Therefore, the area of the rectangle is x(5x)=84.

Solve for x:

6x=84

*Divide both sides by 6*

x=14

So, the width of the rectangle is 14.  To find the length, multiply 14 by 5.  The length is 70.

To find the perimeter, add up the length of each side:

14+14+70+70=168

The perimeter of the rectangle is 168.

step-by-step explanation:

always plug in x. in this case, x equals 4.

i'm going to first solve 4(2+3x)

1) 4(2+3(4)) use pemdas to solve.

i'm going to multiply whats in the parenthesis first, so 3 times 4=12.

2)4 (2+12) i'm then going to multiply 4 by both numbers in the parenthesis (because multiplying comes before adding)

4 times 2= 8.   4 times 12= 48

4) (8+48)= 56 (answer)

i'm then going to solve 8+12x and plug in 4 for x.

1) 8 +12(4)

multiplying comes before adding, so i'm gonna multiply 12 and 4.

12 times 4= 48.

2) 8+48=56

both equal the same!