A rectangular pool has area 2x² + 7x + 3 square hastas. If its width is 2x + 1 hastas find its length Class 9
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A rectangular pool has area 2x² + 7x + 3 square hastas. If its width is 2x + 1 hastas find its length Class 9
Question 1.
A rectangular pool has area 2x² + 7x + 3 square hastas. If its width is 2x + 1 hastas, find its length. Hasta was a unit used to measure length. Class 9
Solution:
Given : Area = 2x² + 7x + 3 square hastas,
Width = 2x + 1 hastas
We know that,
Area = Length × Width
Length = $\frac{\text { Area }}{\text { Width }}$
∴ Length = $\frac{2 x^2+7 x+3}{2 x+1}$
2x² + 7x + 3 = $2\left(x^2+\frac{7}{2} x+\frac{3}{2}\right)$
Since $\frac{1}{2}+3=\frac{7}{2}$ and $\frac{1}{2} \times 3=\frac{3}{2}$, the numbers are $\frac{1}{2}$ and 3.
∴ 2x² + 7x + 3 = 2 (x + $\frac{1}{2}$)(x + 3)
= (2x + 1)(x + 3)
∴ Length = $\frac{(2 x+1)(x+3)}{2 x+1}$
= (x + 3) hastas
..[Cancelling the common factor (2x + 1)]
∴ The length of the rectangular pool is (x + 3) hastas.