If a rectangles length is 4 times its width, ho long is the width and lenth (the perimeter is 90) ?

Answer 1

This is a nice problem! All geometry problems are such fun. . .

Just remember; the perimeter is the sum of all sides! And, because this is a rectangle, opposite sides are the same length, which means you can just multply the sum of one length side and one width side by two to get the perimeter.

2 * (4x + x) = 90
10x = 90
x = 9

or

(4x + 4x + x + x) = 90
10x = 90
x = 9

Therefore, the width of the rectangle is 9 units, and the length is 36 units

Answer 2

width= x
length= 4x (cause it's 4 times the width)

perimeter= (2*width) + (2*length)
perimeter = 2*x + 2*4x
perimeter = 2x + 8x
perimeter = 10x
perimeter = 90 (so you say)
... so 90 = 10 x
90/10 = x
9= x (which is the width)
4x = 36 (which is the length)

try it out... (2*9) + (2*36) = 18+72 = 90

Answer 3

2(l+w)=90
let l=4w (since length is 4 times the width
therefore 2(4w+w)=90
2(5w)=90
10w=90
w=9
therefore length=9*4
=36

Answer 4

l=4w
2l+2w = p

2(4w) + 2w = p
10w=90
w=9
l = 4w = 4(9)=36

Answer 5

let 'L' equal length and'w' equal width.
length is 4 times its width.
L=4w so w+w+4w+4w=90
10w=90
w= 9
L=4w
L=4x9
L=36