The area of a polygon is given by the formula Area = ap/2 where a is the length of the apothem and p is the perimeter. The apothem is a line from the center of the polygon perpendicular to a side.
Depending on the formula you know, you can find the length of a side in 1 of 2 ways.
The first way uses a triangle. Using the radius of the polygon you can create 8 congruent triangles. The center angle will be 360 / 8 = 45 and two side lengths of 20. You can find the length of the base using the law of cosines.
c^2 = 20^2 + 20^2 - 2(20)(20)(cos 45)
c^2 = 400 + 400 - 800(cos 45)
c^2 = 800 - 800(cos 45)
c = sqrt(800 - 800(cos 45)
c = 15.31
The second way is to use this formula:
r = s / (2 sin(180 / n))
20 = s / (2 sin(180/8)
(20)(2)sin(22.5) = s
(40)sin(22.5) = s
s = 15.31
We need to calculate the perimeter. As there are 8 sides (8)(15.31) = 122.48
Now we need to calculate the apothem using
a = S / (2 tan (180 / n)
a = 15.31 / (2 tan (180 / 8))
a = 18.48
Now solve for the area
Area = ap/2
Area = (18.48)(122.48)/2
Area = 1131.72
perimeter = 122.48
area = 1131.72
Let F be the father's current age, and E be Evie's current age.
F = E + 36 this is the current relation between the ages
F + 3 = 5(E + 3) this the relationship in 3 year (hence the + 3)
Then solve by substituting one equation into another:
(E + 36) + 3 = 5(E + 3)
E + 39 = 5E + 15
24 = 4E
6 = E
Evie's current age is 6.
Answer:Examples of Spiral Movement are:
Step-by-step explanation:
1)Cyclone
2)Spiral fern
2 (l + w) = 36
l + w = 18
2x + 7x = 18
9x = 18
x = 2
the length of the sides
l = 2x
l = 2(2)
l = 4
w = 7x
w = 7(2)
w = 14
