Question

Cindy recorded the length of her pencil each day. On the third day, her pencil was 6 inches long, and 5 inches long on the fifth day. Fill in the missing information to find the rate of change and the initial value.

Characteristic

1

Calculation

Formula used to find the rate of change, m

6 - 5 m = 35

2

Rate of change

Select Answer

3

Plugging values ​​into the slope-intercept form, y = mx + b, to solve for the initial value, b

Select Answer

4

Initial value

Answer 1

1. Formula used to find the rate of change, m:
m = (y2 − y1)/(x2 − x1) = (5 − 6)/(5 − 3) = −1/2

2. Rate of change:
−1/2 inch per day

3. Plugging values into y = mx + b to solve for b:
Use (3, 6): 6 = (−1/2)(3) + b → 6 = −1.5 + b → b = 7.5

4. Initial value:
7.5 inches (or 15/2 inches)