The length will be (6x + 15)
The area of rectangle is the product of length and breadth.
Given:
area= 18x² + 69 + 60
width = 3x + 4
Area of rectangle = l*b
18x² + 69 + 60 = (3x + 4)*l
l= 18x² + 69 + 60/( 3x + 4)
l= (6x+ 15)
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