502. Solve the system of equations: 2x - 5y = -7, x - 3y = -5.

Solution:

1. Multiply the second equation by 2: 2(x - 3y) = 2(-5) => 2x - 6y = -10.
2. Subtract the modified second equation from the first equation: (2x - 5y) - (2x - 6y) = -7 - (-10) => 2x - 5y - 2x + 6y = -7 + 10 => y = 3.
3. Substitute the value of y back into the second original equation: x - 3(3) = -5 => x - 9 = -5 => x = 4.

Answer: x = 4, y = 3