Answer: The answer is 8.
Step-by-step explanation: The first step is to convert the expression into figures. We shall call the unknown number Y. So if we are told “the square of a number,” that means Y squared, or better still, Y^2. Further we are told “the difference between the square of a number and 40” and that can be written as;
Y^2 - 40.
Next we are told that this expression is equal to 3 times that number (that is 3Y). That can now be written out as follows,
Y^2 - 40 = 3Y
If we move all expressions to one side of the equation, what we would have is,
Y^2 - 3Y -40 = 0
(Remember that when a positive value crosses to the other side of an equation it becomes negative and vice versa)
We now have a quadratic equation
Y^2 -3Y - 40 = 0
By factorizing we now have
(Y -8) (Y + 5) = 0
Therefore Y - 8 = 0 or
Y + 5 = 0
Hence, Y = 8 or Y = -5
Since we are asked to calculate the positive solution, Y = 8
Answer:
When you see a formula like this, try to operate, so you will see some identities sooner or later. In this case, we have a substraction identity:
\frac{cos ( \alpha - \beta )}{cos \alpha cos \beta } = \frac{cos \alpha cos \beta + sin \alpha sin \beta }{cos \alpha cos \beta } = 1 + tan α · tan β
Step-by-step explanation:
The volume of the box as a polynomial in the variable x is x(12 - 2x)(7 - 2x)
<h3>How to determine the volume?</h3>
The complete question is added as an attachment
From the attached image, we have:
Length = 12 - 2x
Width = 7 - 2x
Height = x
The volume is calculated as:
Volume = Length * Width * Height
Substitute the known values in the above equation
Volume = (12 - 2x) * (7 - 2x) * x
This gives
Volume = x(12 - 2x)(7 - 2x)
Hence, the volume of the box as a polynomial in the variable x is x(12 - 2x)(7 - 2x)
Read more about polynomial at:
brainly.com/question/4142886
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The mean deviation of the ratings is 4.12
<em><u>Explanation</u></em>
The ratings of the ten experts are: 34, 35, 41, 28, 26, 29, 32, 36, 38 and 40
So, the mean of all ratings 
<u>The formula for Mean deviation</u>
, where
is the given data from
to
,
is the mean of the data and
is the total number of data. So.....

So, the Mean deviation 