To find a line perpendicular to 2x - 5y = 20, we need to find the slope of the line. To get the slope, we can solve for y, and get the equation in the form of y=mx + b
So I will solve for y:
So we know the slope is 2/5
The slope of a perpendicular line is the oposite reciprocal of original line. So the oposite reciprocal of 2/5 is -5/2. That will be our new slope
Now that we know the slope we can use the point slope formula to find an equation, then solve for y.