Question

for problems 4-7, sketch a graph that represents the given situation. 4.) the flu virus spreads quickly at first and then more slowly. 5.) the sales of a new cell phone increases at an increasing rate, then the sales remain the same, and then the sales decreases at a constant rate. 6.) the outside temperature decreased at a decreasing rate and then decreased at a constant rate. 7.) mr. sutton provides free math tutoring every day after school. no one comes during the first week of school. over the next 2 weeks, use of the tutoring service gradually increases

Explanation:

Problem 4: Flu Virus Spread

Step1: Set axes

Vertical axis: Number of infected people; Horizontal axis: Time.

Step2: Sketch curve

Start with steep upward slope (fast spread), then slope becomes gentler (slower spread). Curve is concave down.

Problem 5: Cell Phone Sales

Step1: Set axes

Vertical axis: Sales volume; Horizontal axis: Time.

Step2: First segment

Upward curve with increasing slope (accelerating sales).

Step3: Second segment

Horizontal line (constant sales).

Step4: Third segment

Downward straight line (constant decrease rate).

Problem 6: Outside Temperature

Step1: Set axes

Vertical axis: Temperature; Horizontal axis: Time.

Step2: First segment

Downward curve with decreasing slope (slowing decrease rate).

Step3: Second segment

Downward straight line (constant decrease rate).

Problem 7: Tutoring Service Use

Step1: Set axes

Vertical axis: Number of users; Horizontal axis: Time (weeks).

Step2: First week

Horizontal line at 0 (no users).

Step3: Next 2 weeks

Upward curve with gentle slope (gradual increase).

Answer:

1. Concave-down increasing curve
2. Three segments: accelerating increase → flat → constant decrease
3. Two segments: slowing decrease → constant decrease
4. Two segments: flat at 0 → gradual increase