Finding dimensions of a rectangle?
The length of a rectangle is four times it’s width.
If the perimeter of a rectangle is 90cm
What is length and width
Can someone please help me
- coverdalerLv 51 year ago
The perimeter of two of the sides, the length and the width, is 45cm.
We can divide this by five (4+1, because four of the width is the same as one of the length), and find the length.
We then multiply the length by 4 to get the width.
- lenpol7Lv 71 year ago
P = 2(l + w)
But l = 4w
P = 2(4w + w)
P = 2(5w)
P = 10w
90 = 10w
w = 9
l = 4 x 9 = 36
- charlatanLv 71 year ago
- vulcan_alexLv 71 year ago
Let x = the width
Then 4x is the length
The perimeter is than 2x + 8x or 10X
10x = 90 cm, so x = 9 cm. You can do the rest, at least I hope you can.
Algebra requires you to show all your work so I have done so.
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- Mr. SmartypantsLv 71 year ago
Let's use w for the width. The length is 4w.
So what is the perimeter of a rectangle? It's two times its width plus two times its length, right? So 2*w+2*4w, which is 2w+8w, which is 10w. So whatever the perimeter of the rectangle is, the width is 1/10 of it and the length is 4/10 of it.