Problem
3. A rectangle has length $(3 x+7) \mathrm{cm}$ and width $(2 x-1) \mathrm{cm}$. What is the area of the rectangle? $\mathrm{K}$ A) $(5 x+6) \mathrm{cm}^{2}$ C) $\left(6 x^{2}+11 x-7\right) \mathrm{cm}^{2}$ B) $\left(6 x^{2}-7\right) \mathrm{cm}^{2}$ D) $\left(6 x^{2}-11 x-7\right) \mathrm{cm}^{2}$
Solution
Step 1 ：Find the area by multiplying the length and width: \((3x + 7)(2x - 1)\)
Step 2 ：Simplify the expression: \(6x^2 + 11x - 7\)
Step 3 ：The final answer is: \(\boxed{6x^2 + 11x - 7}\)
