1. **State the problem:** Solve the system of linear equations:
$$-2x - 5y = -15$$
$$10x - 4y = 105$$
2. **Formula and rules:** We can solve this system using the elimination or substitution method. Here, we'll use elimination to eliminate one variable.
3. **Multiply the first equation by 5** to align coefficients of $x$:
$$5(-2x - 5y) = 5(-15)$$
$$-10x - 25y = -75$$
4. **Add this to the second equation:**
$$(-10x - 25y) + (10x - 4y) = -75 + 105$$
$$\cancel{-10x} - 25y + \cancel{10x} - 4y = 30$$
$$-29y = 30$$
5. **Solve for $y$:**
$$y = \frac{30}{-29} = -\frac{30}{29}$$
6. **Substitute $y$ back into the first equation:**
$$-2x - 5\left(-\frac{30}{29}\right) = -15$$
$$-2x + \frac{150}{29} = -15$$
7. **Isolate $x$:**
$$-2x = -15 - \frac{150}{29} = -\frac{435}{29} - \frac{150}{29} = -\frac{585}{29}$$
8. **Divide both sides by $-2$:**
$$x = \frac{-\frac{585}{29}}{-2} = \frac{585}{29 \times 2} = \frac{585}{58}$$
9. **Simplify $x$ if possible:**
$$585 = 9 \times 65, \quad 58 = 2 \times 29$$
No common factors, so
$$x = \frac{585}{58}$$
**Final solution:**
$$x = \frac{585}{58}, \quad y = -\frac{30}{29}$$
Linear System 552400
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