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the perimeter of both square and rectangle is 48cm and difference of area of square and rectangle is 4m^2.what is the breadth of rectangle option are 10,12,14

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Answer:

Length and width are 10 cm and 14 cm

Explanation:

If the perimeter of the square is 48 cm, then its side has length


48/ 4=12\ cm

The area of the square is


12* 12=144\ cm^2

If the perimeter of the rectangle is 48 cm, then the sum of the length and the width is


48/ 2=24\ cm

Let

Length = x cm, then

Width = 24 - x cm and the area of the rectangle is


x(24-x)\ cm^2

The difference of area of square and rectangle is
4\ cm^2, then


144-x(24-x)=4\\ \\144-24x+x^2=4\\ \\x^2-24x+140=0\\ \\D=(-24)^2-4\cdot 1\cdot 140=576-560=16\\ \\√(D)=4\\ \\x_(1,2)=(-(-24)\pm 4)/(2\cdot 1)=(24\pm 4)/(2)=12\pm 2=14,\ 10

If
x=14\ cm, then
24-x=24-14=10\ cm.

If
x=10\ cm, then
24-x=24-10=14\ cm

User Jorj McKie
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