Let the distance of the race be d miles. We can now write the equation:

which when solved, gives the value of as 4.2 miles.
The time to walk 4.2 miles at 3 mph is 4.2/3 = 1.4 hours.
The answer is 1.4 hours or 1 hour 24 minutes.
This likely has a pattern. Lets see if we can find it.
The sum of a triangle is 180
The sum of a 4 sided figure is 360
The sum of a 5 sided figure is 3*180 = 540
The sum of a 6 sided figure is 4*180 = 720
==========================
The pattern looks like it it (( n-2 )*180) for any polygon where n is the number of sides of the polygon.
You can convince yourself (but this is not a formal proof) by starting with a 6 sided figure. Pick one point on the figure where 2 sides meet. Draw diagonals to all the points not connected to the point you've chosen. You should be able to get 4 such diagonals. You have created 4 triangles.
4*180 = 720 just what your estimate said.d
8 sides will give 6*180 = 1080 degrees and if you keep going on the above table you will see 1080 come up for 8. I'd post a diagram but I don't know how to upload it.
This procedure is extremely important. There is a new math around where these kinds of problems are solved by reducing them to much simpler questions, and getting an answer for them. The pattern is what you are looking for.
Now you can do the rest of the questions.
Pentagon: (5 - 2) * 180 =
Octagon: (8 - 2) * 180 =
dodecagon (12 - 2)*180=
40 sides 38*180 =
100 sides 98 * 180 =
The equation when rewritten is 
<h3>Calculations and Parameters:</h3>
When we consider the vertex form of the equation:
y= 3(x-2)^2 - (x-5)^2
Expanding further:
2((x-0.5)^2 - 27/4) = 2( (x-0.5)^2)- 27/2
Thus, the final form of the equation would be 
Read more about equations here:
brainly.com/question/17109781
#SPJ4
Answer:
20 cm
Step-by-step explanation:
We can use ratios to solve
We know x = 7 since they are of equal length
x x+7
----- = -------
10 y
7 7+7
----- = -------
10 y
Using cross products
7y = 14*10
7y = 140
Divide by 7
7y/7 = 140/7
y = 20
The volume of a cube = length x width x height. Since they told us this box has a square base, the length and width are both 18 inches.
V = 18 x 18 x 16
V = 5184 cubic inches or in^3