Answer:
Eric's expression is :

and Andrea's is :

In Eric's expression, 20 represents the initial amount of substance with which he has started the experiment.
is the amount of substance left after each time period (in this case, each week).The variable w in this case represents the number of weeks.
Andrea's expression can be written as :

The one outside of parentheses represents the initial amount of the substance. The one inside of parentheses represents 100% of the original amount of the substance. 0.5 represents the 50% of the substance that is lost each time period. The variable w in this case represents the number of weeks.
<u>Answer:</u>
The grade you make on your exam varies directly with the number of correct answers. The constant of variation is 5
<u>Solution:</u>
Given, The grade you make on your exam varies directly with the number of correct answers you get on the exam.
Answering 15 questions correctly will give you a grade of 75 what is the.
We have to find what is the Constant of variation.
Now, according to the given information, grade number of correct answer
Then, grade = c x number of correct answers, where c is constant of variation.
Now, substitute grade = 75 and number of correct answers = 15

Hence, the constant of variation is 5
Answer:
Step-by-step explanation:
FY
A) (3,2),(2,1)<br><br>
B) (3,-2),(-2,1)<br><br>
C) (-3,2),(-2,-1)<br><br>
D) (-3,-2),(2,-1)
bija089 [108]
Answer:
d
Step-by-step explanation:
The answer is 0.2666 when u convert the fraction.So if I were you I would put B.