Given:
Octagon-shaped patio
Side length = 24ft
apothem length = 60ft
Area of a regular octagon = 2 * a² * (1 + √2)
a = side length
A = 2 * (24ft)² * (1 + √2)
A = 2 * 576ft² * (1 + 1.414)
A = 2 * 576ft² * 2.414
A = 2,780.93 ft²
Answer:
Step-by-step explanation:
Nice summary problem.
<AEC
- AEC = 360 - 243.5 = 116.5
- The number of degrees in 1 rotation of a circle = 360o. You have accounted for 243.5 degrees. What is left over is the answer.
<EAD and <ECD
Both of these are tangents to a circle. Tangents meet radii at 90 degree angles.
<EAD = <ECD = 90 degrees
<ABC
<ABC is 1/2 the central angle. The Central angle is <AEC
- < AEC = 116.5
- <ABC = 1/2 * 116.5
- <ABC = 58.25
<ADC
There are 2 ways of doing this. You should know both of them.
<em><u>One</u></em>
All quadrilaterals = 360 degrees. You know three of the angles. You should be able to find ADC
- <ADC + 90 + 90 + 116.5 = 360 Add the four angles together.
- <ADC + 296.5 = 360 Combine terms on the left
- <ADC = 360 - 296.5 Subtract 238.25 from both sides
- <ADC = 63.5 Answer
<em><u>Method Two</u></em>
<ADC = 1/2 (major Arc - Minor Arc) This formula is fundamental to circle / tangent properties. The Major arc is the larger of the two parts of the circumference of a circle. The Minor arc is the smaller.
- <ADC = 1/2(243.5 - 116.5)
- <ADC = 1/2(127)
- <ADC = 63.5
The little lines in each side show that the sides are the same length but you also need to find the length of the smaller side which isn’t the same. For this imagine that the shape is split into a square and a triangle and you need to find the long side of the triangle using Pythagoras
a^2 + b^2 = c^2
20^2 + 20^2 = 800
Square root of 800 = 28.3
Then do 28.3-20=8.3
So I think the answer is 20+20+20+20+20+8.3=108.3 cm
Answer:
A.)130 80
Step-by-step explanation:
1y/3x
-8x/1xy
answer:130 80
Answer: (4, -9)
<u>Step-by-step explanation:</u>
Use elimination method. Manipulate one (or both) equations to eliminate one of the variables and solve for the remaining variable. <em>I will be eliminating y</em>
6x + y = 15 → 2(6x + y = 15) → 12x + 2y = 30
-7x - 2y = -10 → 1(-7x + 2y = -10) → <u> -7x - 2y = -10</u>
5x = 20
x = 4
Next, replace "x" with "4" into either equation and solve for y.
6(4) + y = 15
24 + y = 15
y = -9
<u>Check:</u>
Plug in x = 4 and y = -9 into the other equation to verify it makes a true statement.
-7x - 2y = -10
-7(4) - 2(-9) = -10
-28 - -18 = -10
-28 + 18 = -10
-10 = -10 