Answer:
(C) 100
Step-by-step explanation:
The average of a data set is just all the numbers added up divided by the amount of numbers.
If we already have 4 pieces of data and we're looking for one more, we have 5 data pieces.
This means that the sum of all of the numbers in the data set will be 
if the mean is 91.
We can find the missing value by adding up what we know and subtracting from 455.
So Abby needs a 100% on her fifth history quiz to have an average of 91 on all her quizzes.
Hope this helped!
Answer:
None of them are irrational.
Step-by-step explanation:
An Irrational Number is a real number that cannot be written as a simple fraction.
Therefore:
-4 can be written as -4/1
2/9 is already in fraction
8.26 can be written as 826/100
11 can be written as 11/1
None of them are irrational.
However numbers like 
are irrational as they can not be represented as fractions.
That's not a linear system, but you have an awesome school system for giving you this problem.
Multiply by 6xy to clear the fractions.
That's a second degree equation, also known as a conic. That one happens to be a hyperbola.
Let's clear the fractions from the second equation, multiplying out common denominator xy:
We are being asked to find the meet of two hyperbolas, so we expect two answers, a quadratic equation.
Substituting,
We have to rule out x=0 because it's in the denominator.
Answer: (44/19, 33/20)
Answer:
a = -8
Step-by-step explanation:
19 = -3a - 5
Add 5 to both sides.
24 = -3a
Divide both sides by -3.
-8 = a
Switch sides.
a = -8
Answer is 11
Just trust me
