Answer:
A rule of polygons is that the sum of the exterior angles always equals 360 degrees. Since it is a regular octagon, so each of the interior angles of octagon are equal. ((n-2)*180)/n where n is the number of sides of the polygon.for example in case n=8 for an octagon, so we get:
((8-2)*180)/8 => (6*180)/8 => 1080/8 = 135 degrees. This means that each interior angle of the regular octagon is equal to 135 degrees.
Each exterior angle is the supplementary angle to the interior angle at the vertex of the polygon, so in this case each exterior angle is equal to 45 degrees. (180 - 135 = 45). Remember that supplementary angles add up to 180 degrees.
And since there are 8 exterior angles, we multiply 45 degrees * 8 and we get 360 degrees.
This technique works for every polygon, as long as you are asked to take one exterior angle per vertex.
If you would like to know which expression represents the amount of time Joe exercises, you can calculate this using the following steps:
Keith ... x hours a week
Troy ... three hours less than Keith: x - 3
Joe ... two times more than Troy: 2 * (x - 3)
The correct result would be D) 2 * (x - 3).
Answer:
110 cm^2
Step-by-step explanation:
The first thing that you need to do is find the area of triangle AFE. The area of a triangle is always base*height/2. So in this case, that would be 10*6 divided by 2, which is 30 cm. Next, you will need to know the area of triangle ECB. Using that same formula, you will get 8*10/2, which is 40 cm. Finally, you will need to find the area of the whole rectangle. The area of a rectangle is always the length times the width. In this case, you would have 10*18, which is 180 cm. To get your final answer, you need to subtract the areas of the unshaded area from the whole area. That would be 180-(30+40), which is 110 cm. I hope this helped!