Answer:
first one
28.26 im not 100% correct i dont think
<u>Define x:</u>
Let the number of children tickets be x.
Children tickets = x
Adult tickets = 2x
<u>Construct the equation:</u>
4x + 7(2x) = 108
4x + 14x = 109
18x = 108
x = 6
x = 6
2x = 12
Answer: 6 children tickets and 12 adult tickets.
Where <em>x </em>is the number of books sold, <em>i </em>is income, and <em>c </em>is cost:
<em>c = 4x + 3500 </em> ($4 per book plus the 3500 flat marketing fee)
<em>i = 15x </em>($15 per book)
You are looking for the point where these intersect: the intersection is where the income is equal to the cost, and at any point after that the income is greater than the cost. So, set the equations equal to each other:
<em>4x + 3500 = 15x </em>
subtract 4x from both sides
<em>3500 = 11x</em>
divide both sides by 11
<em>x = 318.181818</em>
So, you would have to sell a minimum of 319 books in order to make a profit.
Answer
A = C2 / (4 π) for the first question. C = 2*π*square root of (A/π). for the second question.
Step-by-step explanation:
The area of a circle is given by the formula A = π r2, where A is the area and r is the radius. The circumference of a circle is C = 2 π r.
If we "solve for r" in the second equation, we have r = C / (2 π ). Now we use this to replace r in the first equation: A = π [ C / (2 π ) ]2.
When we simplify this, we get A = C2 / (4 π).
Now you can put your value of C into this equation and find A.