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Question
The area of a rectangle is x2 + 7x + 12. If its breadth is (x + 3), then find its length.
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Solution
Let the length of the rectangle be l.
Given, area of a rectangle = x2 + 7x + 12
And breadth = x + 3
We know that,
Area of rectangle = Length × Breadth
⇒ x2 + 7x + 12 = l × (x + 3)
⇒ `l = (x^2 + 7x + 12)/(x + 3)`
= `(x^2 + 4x + 3x + 12)/(x + 3)`
= `(x(x + 4) + 3(x + 4))/(x + 3)`
= `((x + 4)(x + 3))/(x + 3)`
= x + 4
Hence, the length of rectangle = x + 4
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