What is the slope of the line perpendicular to the line with equation 4x-5y+13=0

m = - 5/4

Step-by-step explanation:

If two lines are perpendicular, their slopes are negative reciprocals, which means that their product is -1

We can write the equation

4*x - 5*y + 13  = 0

as:      5*y  =  4*x  + 13      or    

y  = (4/5)*x  + 13        (1)

Equation (1) is the equation of a straight line in its slope point form, 4/5 is the slope, according to this  the slope of a perpendicular line is

-5/4

the answer is c. 23/3