Given:
The table of values is
Number of Students : 7 14 21 28
Number of Textbooks : 35 70 105 140
To find:
The rate of change and showing that the ratios of the two quantities are proportional and equivalent to the unit rate.
Solution:
The ratio of number of textbooks to number of students are




All the ratios of the two quantities are proportional and equivalent to the unit rate.
Let y be the number of textbooks and x be the number of students, then

Here, k=5.


Hence the rate of change is constant that is 5.
Answer: 150 students walk to school
Step-by-step explanation: 75%=0.75
200 multiplied by 0.75
200×0.75=150 students
Or
75%=3/4
3/4 of the children walk to school
3/4×200=3/4×200/1=150
The slope is undefined, if the line is vertical the slope equation m=(change in y)/(change in x) becomes undefined because youd be dividing by zero
Answer: 
Step-by-step explanation:
Given
The unit cost is given by

find the derivative of the unit cost and equate it to zero to obtain the minimum value

Substitute 140 for
in the cost function, we get
![C(140)=0.6[140]^2-168(140)+30,389\\C(140)=11,760-23,520+30,389\\C(140)=\$18,629](https://tex.z-dn.net/?f=C%28140%29%3D0.6%5B140%5D%5E2-168%28140%29%2B30%2C389%5C%5CC%28140%29%3D11%2C760-23%2C520%2B30%2C389%5C%5CC%28140%29%3D%5C%2418%2C629)
Answer:
D
Step-by-step explanation: