Hello!
The mean is the average of the numbers
To find the average you add them all up and divide the sum by the amount of numbers added
87 + 72 + 99 + 93 + 84 = 435
Divide the sum by the amount of numbers added
435 / 5 = 87
The answer is 87
Hope this helps!
Answer:

Step-by-step explanation:


------------------------------------------------------------------------
Change the divide fraction to multiplication fraction :
------------------------------------------------------------------------

------------------------------------------------------------------------
Combine into single fraction :
------------------------------------------------------------------------

------------------------------------------------------------------------
Reduce to simplest form :
------------------------------------------------------------------------
First you do the multiplication ( 4 x 7) then add 6
28 + 6 = 34
The minimum happens at x = -b/2a
x = -30 / 2(3) = -30/6 = -5
Now replace x in the equation with -5 and solve:
3(-5)^2 + 30(-5) +27 = 75 - 150 + 27 = -48
The minimum is at (-5,-48)