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
4+3.5=7.5
7.5x =180
180/7.5
=24 (answer)
You can determine midpoint by
x-midpoint = (x₁ + x₂)/2
y-midpoint = (y₁ + y₂)/2
Given from the question
x-midpoint = -6
x₁ = -7
y-midpoint = 5
y₁ = 8
Asked from the question
(x₂, y₂)
Solution
Find x₂, input the value of x₁ and x-midpoint to the formula
(x₁ + x₂)/2 = x-midpoint
(-7 + x₂)/2 = -6
-7 + x₂ = -6 × 2
-7 + x₂ = -12
x₂ = -12 + 7
x₂ = -5
Find y₂, input the value of y₁ and y-midpoint to the formula
(y₁ + y₂)/2 = 5
(8 + y₂)/2 = 5
8 + y₂ = 5 × 2
8 + y₂ = 10
y₂ = 10 - 8
y₂ = 2
Answer
P₂ = (-5,2)
Answer: x=-303
Step-by-step explanation:
x+310=7
We move all terms to the left:
x+310-(7)=0
We add all the numbers together, and all the variables
x+303=0
We move all terms containing x to the left, all other terms to the right
x=-303
Answer:
We have been given that the upstream speed is and the down stream speed is .
Let the fisherman traveled a distance of x miles.
The total time of the trip is 6 hours.
Relations between speed (s), time (t) and distance (d) is
Hence,
Time upstream + time downstream = 6
lcm = 10
=>
Cross multiplying,
x = 20 miles .. Answer.
Step-by-step explanation: