Answer:
Hi the answer is A, hopefully i helped you
Although x ² and x both have the variable x, you can’t add them together. So x + x + x + x is 4x and we just leave x ² the same. So the simplified expression is x ² + 4x. I hope this helped!!
For this case we have the following quadratic functions:
Revenue: 
Cost: 
Then, we observe that the profit is given by the following mathematical relationship:

Substituting values we have:

Making the corresponding calculations we have:

Answer:
An expression that represents the profit is:

A. Constant of proportionality in this proportional relationship is; k=5
B. Equation to represent this proportional relationship is : c=t/k
Step-by-step explanation:
A.Given that : the amount she pays each month for international text messages is proportional to the number of international texts she sends, then
$3.20 k = 16 ---------where k is the constant of proportionality
k= 16/3.20 =5
k=5
B. Let c be the cost of sending the texts per month and t be the number of texts sent per month , so
c=t/k
c=t/5 ---------- is the proportionality relationship.
For t=16 , c= 16/5 =$3.20
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Proportionality :brainly.com/question/11490054
Keywords: cell phone plan, month, international texts, proportional,paid
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2) 25/48 All you do is multiply both.
1) she sold 5 children and 10 adult. 5 *5 equals 25. You double 5 to get twice as many tickets for adults and get 10. 8 *10 equals 80. 80 + 25= $105