Answer :
Final answer:
The length of the rectangle is 5x^2 + 7x - 4.
Explanation:
In this mathematics problem, the length of a rectangle is to be found. Given is that the area of the rectangle, 15x^(4)+21x^(3)-12x^(2), and the width is 3x^(2). We know that the area of the rectangle is the product of its length and width. So, to find the length, we divide the area by the width.
That gives us:
Length = (15x^(4)+21x^(3)-12x^(2)) / 3x^(2).
After simplifying this, we get:
Length = 5x^(2) + 7x - 4. So, the length of the rectangle is 5x^2 + 7x - 4.
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