Answer:
66.46
Step-by-step explanation:
I can't read that language but I'll guess it says write a second degree equation then solve for n when d=10.



Answer: n² - 3n - 20 = 0
That doesn't factor so there is no integer n solution.
That means there are no polygons with 10 diagonals.

Let's say "c" is a constant, hmmmm any constant, for any value whatsoever of "x", "y" is always that constant, for example, say c = 3, thus y = 3, so a table for it will look like

now, if you plot those points, it'd looks like the picture below.
Answer:
The equation is 
Step-by-step explanation:
If we want a line parallel to the line in the problem it will have the same slope. The equation given in the problem is already in slope intercept form so we can take the slope for the new equation directly from this equation.
The slope-intercept form of a linear equation is: 
Where m is the slope and b is the y-intercept value.

Therefore the slope is

We can now use the point-slope formula to write the equation of the parallel line:
The point-slope formula states:

Where m is the slope and
is a point the line passes through.
Substituting the information from the problem gives:


Or, we can solve for y to put the equation in slope-intercept form:




1 book is 17.55
2 books is 16.70
3 books is 15.85
4 books is 15
5 books is 4.15
6 books is 4.30
7 books is (3.55)