10. Fish don't drown (; nice try tho
Answer:
Step-by-step explanation:
given a point
the equation of a line with slope m that passes through the given point is
or equivalently
.
Recall that a line of the form
, the y intercept is b and the x intercept is
.
So, in our case, the y intercept is
and the x intercept is
.
In our case, we know that the line is tangent to the graph of 1/x. So consider a point over the graph
. Which means that 
The slope of the tangent line is given by the derivative of the function evaluated at
. Using the properties of derivatives, we get
. So evaluated at
we get 
Replacing the values in our previous findings we get that the y intercept is

The x intercept is

The triangle in consideration has height
and base
. So the area is

So regardless of the point we take on the graph, the area of the triangle is always 2.
Answer: 
Step-by-step explanation:
For this exercise you need to use the following formula for calculate the area of regular polygon:

Where is "s" the length of any side, "n" is the number of sides.
Int this case you know that it is regular pentagon, which means that it has five sides. Then you can identify that the values of "n" and "s":

Therefore, substituitng values into the formula, you get that the area f the pentagon is:

State the given in the question
Given that the sum of a number and 3 is subtracted from, the result is 5
State what is to be found in the question
We are to find the number. In other to achieve this, we would follow the steps below:
Step 1: Represent the number with an unknown
Let x represent the number
Step 2: Interpret the given statement mathematically
If x is the number, then the sum of the number and 3 would be

Then the sum of a number and 3 subtracted from 10 would be

Finally, when the sum of a number and 3 subtracted from 10, the result is 5, would be

Step 3: Solve for x in the mathematical interpretation of the given statement
The value of x is as calculated as shown below:

Hence, the number is 5
Answer:
Step-by-step explanation:
12x+18=75
-18=-18
12x= 57
Divide by 12.
57/12=4.75
Grace can buy 5 books including the reference book