Answer:
The third score must be larger than or equal to 72, and smaller than or equal 87
Step-by-step explanation:
Let's name "x" the third quiz score for which we need to find the values to get the desired average.
Recalling that average grade for three quizzes is the addition of the values on each, divided by the number of quizzes (3), we have the following expression for the average:

SInce we want this average to be in between 80 and 85, we write the following double inequality using the symbols that include equal sign since we are requested the average to be between 80 and 85 inclusive:

Now we can proceed to solve for the unknown "x" treating each inaquality at a time:

This inequality tells us that the score in the third quiz must be larger than or equal to 72.
Now we study the second inequality to find the other restriction on "x":

This ine
quality tells us that the score in the third test must be smaller than or equal to 87 to reach the goal.
Therefore to obtained the requested condition for the average, the third score must be larger than or equal to 72, and smaller than or equal 87:
The answer would be 0 solutions.
Here, we see <em>|</em><em />x+6<em>|</em><em /> = 2.
Oh wow! A foreign object!
|x+6|... two lines... what is that?
That is called absolute value. Whatever is inside the two lines, must have a positive answer!
Let's pretend we have a machine that has this absolute value function activated.
What we put in, we must get a positive answer out.
Let's put in -6.
-6 ==> BEEP BEEP ==> 6
Let's try 3.
3 ==> BEEP BEEP ==>3
Whatever we put in, if it is negative or positive, what comes out is always positive.
So, for how many values <em>x</em> is |x+6|=-2 true?
None, because the answer <em>must</em><em /> be positive!
-2 is not positive, <em>2</em><em /> is.
Step-by-step explanation:
3x(x2 + 2x – 6) + 4(x2
– 6x + 2)
Answer:

Step-by-step explanation:
x+2/3x - 1/x-2 = x-3/3x

LCD is (3x)(x-2). so we multiply the whole equation by LCD

We multiply each term by LCD


Answer:
4 : 3
Step-by-step explanation:
Because when you divide 24 by 6 and divide 18 by 6. It would be 4 : 3