
(a) m = 3
(b) y - 20 = 3x - 15
(c) y = 3x + 5

(a) To find the slope of the line passing through the points (5, 20) and (0, 5), we can use the formula:
slope (m) = (y2 − y1) / (x2 − x1)
Let's substitute the given values into the formula:
m = (20 - 5) / (5 - 0)
m = 15/5
m=3
Therefore, the slope of the line is 3.
(b) To write the equation of the line in point-slope form, we can use the formula:
y - y1 = m(x-x1)
Let's substitute one of the given points, (5, 20), into the formula:
y - 20 = 3(x-5)
Simplifying the equation:
y - 20 3x - 15
This is the equation of the line in point-slope form.
(c) To write the equation of the line in slope-intercept form, we need to solve the equation obtained in part (b) for y.
y - 20 = 3x - 15
Adding 20 to both sides of the equation:
y = 3x - 15 + 20
y = 3x + 5
Therefore, the equation of the line in slope-intercept form is y = 3x + 5.