A general equation to use for this situation is y = mx + b.
For this question, we can assume that y is total cost, m is cost per balloon, x is the amount of balloons, and b as the service fee; so we can set the equation up:
y = (4.50)x + 12
And we can further plug in the total cost to find the number of balloons purchased for the party:
79.50 = (4.50)x + 12
Now we can solve for x (number of balloons):
67.50 = (4.50)x
x = 15
The total number of balloons purchased for the party is 15.
Answer: 24, 44, and 66 
Step-by-step explanation:
Check all of the possible combinations of the faces:
6 × 4 = 24
11 × 4 = 44
11 × 6 = 66
So the answers are 24, 44, and 66 
Answer:
Yes
Step-by-step explanation:

560 / 28 = 20....so the driver travels 20 miles per gallon
on 35 gallons......35 * 20 = 700 miles <==
or u can also do it this way...
560/28 = x / 35....560 miles to 28 gal = x miles to 35 gal
cross multiply because this is a proportion
(28)(x) = (560)(35)
28x = 19600
x = 19600/28
x = 700 miles <==
so u can either do it by finding the unit rate or by making a proportion. either way will result in the same answer.
Answer: +23
Step-by-step explanation:
It would be 23 because the difference between -19 and 4 is 23