1. **Problem statement:** Solve the system of equations
$$\begin{cases}(3x+2)(2y-3)=6xy\\(4x+5)(y-5)=4xy\end{cases}$$
2. **Rewrite each equation:**
- First equation: Expand left side
$$ (3x+2)(2y-3) = 6xy $$
$$ 6xy - 9x + 4y - 6 = 6xy $$
3. **Simplify first equation:**
Subtract $6xy$ from both sides:
$$ \cancel{6xy} - 9x + 4y - 6 = \cancel{6xy} $$
$$ -9x + 4y - 6 = 0 $$
4. **Rewrite second equation:**
$$ (4x+5)(y-5) = 4xy $$
$$ 4xy - 20x + 5y - 25 = 4xy $$
5. **Simplify second equation:**
Subtract $4xy$ from both sides:
$$ \cancel{4xy} - 20x + 5y - 25 = \cancel{4xy} $$
$$ -20x + 5y - 25 = 0 $$
6. **Rewrite simplified system:**
$$ \begin{cases} -9x + 4y - 6 = 0 \\ -20x + 5y - 25 = 0 \end{cases} $$
7. **Solve the system:**
Multiply first equation by 5 and second by 4 to align $y$ coefficients:
$$ \begin{cases} -45x + 20y - 30 = 0 \\ -80x + 20y - 100 = 0 \end{cases} $$
8. **Subtract first from second:**
$$ (-80x + 20y - 100) - (-45x + 20y - 30) = 0 $$
$$ -80x + 20y - 100 + 45x - 20y + 30 = 0 $$
$$ -35x - 70 = 0 $$
9. **Solve for $x$:**
$$ -35x = 70 $$
$$ x = \frac{70}{-35} = -2 $$
10. **Substitute $x=-2$ into first simplified equation:**
$$ -9(-2) + 4y - 6 = 0 $$
$$ 18 + 4y - 6 = 0 $$
$$ 4y + 12 = 0 $$
$$ 4y = -12 $$
$$ y = -3 $$
11. **Check solution in original equations:**
- Check first:
$$ (3(-2)+2)(2(-3)-3) = ( -6 + 2)(-6 - 3) = (-4)(-9) = 36 $$
$$ 6(-2)(-3) = 6 \times -2 \times -3 = 36 $$
- Check second:
$$ (4(-2)+5)(-3 - 5) = (-8 + 5)(-8) = (-3)(-8) = 24 $$
$$ 4(-2)(-3) = 24 $$
Both checks are correct.
**Final answer:** The solution is $\boxed{(-2;-3)}$ which corresponds to option B.
Solve System 22741F
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