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A rectangle has a length of X +5 and a width of X -5 and has an area of 15 square units find the length and width of the rectangle.

User Ethan Fang
by
4.4k points

2 Answers

3 votes

Answer:L=11.3

W=1.3

Explanation:

A rectangle has a length of X +5 and a width of X -5 and has an area of 15 square-example-1
User Mohsen Mokhtari
by
4.9k points
9 votes

Given :-

  • Length of rectangle = x + 5
  • width of rectangle = x - 5
  • Area of rectangle = 15 unit²


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To find:-

  • Actual length and width of rectangle


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Solution:-

So to find actual length and width of rectangle, we need to find value of x.


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we know:-


\bigstar \boxed{ \rm Area~of \: rectangle = length * width}


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So:-


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\hookrightarrow \sf Area~of \: rectangle = length * width \\


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\hookrightarrow \sf 15=(x + 5)(x - 5) \\


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\hookrightarrow \sf 15=x (x - 5) +5(x - 5)\\


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\hookrightarrow \sf 15=x^2 - 5x +5(x - 5)\\


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\hookrightarrow \sf 15=x^2 - 5x +5x - 25\\


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\hookrightarrow \sf 15=x^2 - \cancel {5x} +\cancel {5x} - 25\\


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\hookrightarrow \sf 15=x^2 -0 - 25\\


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\hookrightarrow \sf 15=x^2 - 25\\


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\hookrightarrow \sf 15 + 25=x^2 \\


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\hookrightarrow \sf 15 + 25=x^2 \\


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\hookrightarrow \sf 40=x^2 \\


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\hookrightarrow \sf x^2 = 40\\


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\hookrightarrow \sf x = √(40)\\


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\hookrightarrow \sf x = √(2 * 2 * 10)\\


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\hookrightarrow \sf x = 2 √(10)\\


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\hookrightarrow \sf x = 2 * 3.16\\


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\hookrightarrow \sf x = 2 * 3.16\\


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\hookrightarrow \bf x = 6.32(approx)\\


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  • Length = x + 5
  • Length = 6.32 + 5
  • Length = 11.32 (units)


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  • Breadth = x - 5
  • Breadth = 6.32 - 5
  • Breadth = 1.32 (units)
User Sumit Jha
by
4.7k points