Explanation:
Given a point (4,80) and a slope, m = 60, these can be used to formulate the equation of the graph. Using the point-slope formula:
y - y1 = m(x - x1)
y - 80 = 60(x - 4)
y - 80 = 60x - 240
y = 60x -160
Taking the x and y-intercepts:
At y = 0
0 = 60x - 160
x = 2.7
At x = 0
y = 60(0) - 160
y = -160