You would need to solve for y first. To solve for y you would need to know this formula, y = mx + b.
2x - 5y = 10 subtract 2x from both sides
-5y = -2x + 10 divide by -5 from both sides
y = 2/5x - 2
Then to find the slope, you would need to know what m is.
y = 2/5x - 2 is already in the formula y = mx + b.
The answer is: slope = 2/5