The mean is the sum of all numbers divided by the number of numbers. We can set up an equation:

Where 'x' is the next quiz score she need. Solve for 'x'. Multiply 5 to both sides:

Add:

Subtract 322 to both sides:

So her next quiz score needs to be 73 in order to have a mean score of 79 on all her quizzes.
Answer:
-457
i think i used a calculator
hope this helps
Step-by-step explanation:
Answer:
x - 3y + z
Step-by-step explanation:
Terms are just names for objects inside the equation -- anything that isn't an operation. A coefficient the is the number a given term (variable) is being mulitpled by. In this case, -3 for y, and 1 for. x. We can deduce from this the start of the expression (x has no coeff. bc of multiplicative identity)
x - 3y
We know we are missing one term, and we also know that the third term cannot be constant, so it must be another variable. In this case I have chosen Z, in theory it shouldn't really matter but z is the best variable name in this case.
Answer:
y = 9
Step-by-step explanation:
Using the sine ratio in the right triangle and the exact value
sin45° = 
sin45° =
= 
Multiply both sides by y
y × sin45° = 9, that is
y ×
= 9
Multiply both sides by 
y = 9
For this case we propose a system of equations:
x: Represents the amount of small popcorn tubs
y: Represents the amount of large popcorn tubs
According to the data we have to:
(Spending all the money in your wallet)
(Buying 7 popcorn tubs)
From the second equation we have:

Substituting in the first equation:

Thus, Katie can buy 3 large tubs of popcorn.
So:

In addition, you can buy 4 small tubs of popcorn.
Answer:
3 large popcorn tubs.
4 small popcorn tubs.