Line p passes through the point (5, 1) and has a slope of -4/5.
what is the equation of line p in standard form?

Your first step is to write this expression in point-slope form, which is as follows:

y - y1 = m(x - x1)

y1 and x1 are where you put the x and y values of your coordinates. m is the slope.

Your expression would be written like this in point-slope form:

y - 1 = -4/5(x - 5)

To get to standard form (Ax + By = C), simply simplify the expression as follows.
Distribute the right side:

y - 1 = -4/5x + 4

Add one to both sides:

y = -4/5x + 5

Now you want to get x and y on both sides:

Add -4/5x:

4/5x + y = 5

To make this better, cancel the fractions by multiplying the equation by 5:

4x + 5y = 20

That is your final answer!