please help me I really need help in my math work

we need to know the formula of the area of a rectangle
[tex]A=l\cdot w\text{ }[/tex]we already know A and l we need to clear w
[tex]w=\frac{A}{l}=\frac{2x^2+5x-12}{2x-3}[/tex]we need to do the division
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