Since 1990, when the average monthly price for basic cable TV programming in one country was $15.91, the cost has risen by about $1.22 a year. Write an equation in slope-intercept form to predict cable TV costs in the future. Use t to represent time in years after 1990 and C to represent the average basic monthly cost.

Question

Quizplus · Accepted Answer

Using the point-slope formula, where m is the slope and (t1, C1) is a point on the line:
C - 15.91 = 1.22(t - 1990)
C = 1.22t - 2401.09
This equation is already in slope-intercept form (y = mx + b), where m = 1.22 and b = -2401.09. Therefore, the best choice is B, which matches this equation.

Since 1990, When the Average Monthly Price for Basic Cable