The length of a rectangle is four times its width. If the perimeter of the rectangle is 70in , find its area.?

2 (L + W) = 70

2 (4W + W) = 70

5W = 35

W = 7 in

L = 28 in

A = 196 in²

L = 4W "The length of a rectangle is four times its width."

2L + 2W = 70 "the perimeter of the rectangle is 70in"

Multiply #1 by -2 and add to #2.

2L + 2W = 70

-2L = -4W

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0 + 2W = 70 - 4W Add 4W to both sides.

6W = 70

W = 70/6 = 35/3 = 11 2/3 inches

L = 4W = 140/3 = 46 2/3 inches

A = LW = 35/3 x 140/3 = 4900/9 = 4896 4/9 square inches

Get a ruler in your hands. Measure things until you start to understand how a ruler works. Measure some stuff and figure out where the center is. Say you measure a book and it's 7/8" thick. You look at your ruler and see that every eighth is divided into two sixteenths, so obviously half of 7/8" is going to be 7/16". If you write that out you have 1/2 x 7/8 = 7/16. And you notice that 1/2 is divided into 2/4 and then into 4/8 and so on, so you can convert anything to anything by multiplying all the numbers on top and then all the numbers on bottom.

Other rulers are divided into 10 and 100 parts. But an inch is still and inch, so anything on one ruler can be translated to the other ruler. A half inch on one ruler is 5/10 or 50/100 on the other. An eighth inch is just 12.5 marks when you have 100 marks per inch. A metric ruler divides an inch into 25.4 parts, so a half inch would be 12.7 of those parts. Pretty simple, isn't it? Practice this a bit and people will think you went to wizard school.

Let length = l and width = w. Therefore, as given, l = 4w. As a rectangle's perimeter is given by 2l + 2w, we can substitute then new value of l to give the perimeter of the recatangle to be 10w.

Therefore, 10w = 70", and so the width, w =7". We know that the length is 4 x width, so 28".

This means the area is 7 x 28 = 196 inches squared.

Perimeter = 2l + 2w

l=4w

2(4w)+2w = 70

10w = 70

w = 7

l=28 (w*4)

2(7) + w(28) = 14+56 = 70

Area = l*w = 7*28 = 196

Width is 7 inches

Length is 28 inches

so the area is 196 inches squared

Im guessimg in is inches but it dosent matter

a:b=4:1 => a=4b

2a+2b=70

8b+2b=70

b=7

a=b*4=7*4=28

A=a*b=7*28=196 in^2

l=4w

10w=70

w=7 in

l=28 in

width is 7 inches,

length is 28 inches,

the area is l x w, so 28 inches x 7 inches =

196 square inches.