Understanding Phone Company Charges and Inequalities

The video tutorial explains how to solve a problem involving a phone company's charges for daytime and nighttime minutes. It introduces variables for day and night minutes, converts dollars to cents, and formulates an inequality to represent the situation. The tutorial then demonstrates how to graph the inequality, find intercepts, and determine the solution region by shading the appropriate area on the graph. The example helps viewers understand how to solve linear inequalities graphically.

What is the cost per minute for daytime calls according to the phone company?

• 5 cents

• 20 cents

• 15 cents

• 10 cents

How many cents are equivalent to 10 dollars?

• 2000 cents

• 100 cents

• 500 cents

• 1000 cents

What does the variable 'D' represent in the inequality?

• Total cost in cents

• Total cost in dollars

• Number of night minutes

• Number of day minutes

Which equation represents the borderline of the inequality?

• 5D + 20N > 1000

• 20D + 5N > 1000

• 5D + 20N = 1000

• 20D + 5N = 1000

What is the D-intercept of the line 20D + 5N = 1000?

• D = 100

• D = 50

• D = 20

• D = 200

What is the N-intercept of the line 20D + 5N = 1000?

• N = 100

• N = 20

• N = 50

• N = 200

Why is the line 20D + 5N = 1000 dashed in the graph?

• It is a solid line

• It represents an equation, not an inequality

• The inequality is less than

• The inequality is greater than

Which quadrant is considered when graphing the inequality?

• First quadrant

• Second quadrant

• Fourth quadrant

• Third quadrant

What does shading above the line in the graph represent?

• Charges exactly 10 dollars

• Charges more than 10 dollars

• Charges less than 10 dollars

• No charges

What is the significance of the point (0, 0) in the graph?

• It satisfies the inequality

• It does not satisfy the inequality

• It is the endpoint

• It is the midpoint