Final answer:
To solve the system of equations 7y + 10x - 8 = 0 and 2y - 5x - 18 = 0, first isolate y in the first equation, then substitute the value of y into the second equation and solve for x. Finally, substitute the value of x back into the first equation to solve for y.
Step-by-step explanation:
To solve the system of equations:
7y + 10x - 8 = 0
2y - 5x - 18 = 0
- Rearrange the first equation to isolate y: 7y = -10x + 8
- Divide both sides of the equation by 7 to solve for y: y = -10/7x + 8/7
- Substitute this value of y into the second equation: 2(-10/7x + 8/7) - 5x - 18 = 0
- Simplify and solve for x: -20/7x + 16/7 - 5x - 18 = 0
- Combine like terms: -20/7x - 5x - 2 = 0
- Combine the x terms: -35/7x = 2
- Divide both sides by -35/7 to solve for x: x = -2 * 35/7 = -10
- Substitute this value of x back into the first equation to solve for y: 7y + 10(-10) - 8 = 0
- Simplify and solve for y: 7y - 100 - 8 = 0
- Combine like terms: 7y - 108 = 0
- Add 108 to both sides: 7y = 108
- Divide both sides by 7 to solve for y: y = 108/7 = 15 3/7
Therefore, the solution to the system of equations is x = -10 and y = 15 3/7.