Ch. 11 First Quiz

Question 1

Circumference

Answer 1

C=πd or C= 2πr

Question 2

Only multiply π when…

Answer 2

1. Instructed to do so
2. In a real-life problem
3. If the author has already done it

Question 3

How to find the arc length in a circle

Answer 3

Central angle/360 * circumference

Question 4

How to find the perimeter of polygons

Answer 4

Circumference of the pieces π + straight pieces
Only need sides that are actually on the outside

Question 5

How to convert angle measures to radians

Answer 5

180/π = angle measure/x (radians)
Solve for x

Question 6

How to convert radians to angle measures

Answer 6

Replace π with 180 degrees and solve

Question 7

Area of a circle

Answer 7

πr²

Question 8

How to find the area of a section of a circle

Answer 8

A= x(angle of the section)/360 * πr²

Question 9

Population Density

Answer 9

Number of people/area of land (use π)

Question 10

How to solve a Shade

Answer 10

Everything in a circle minus what’s included

Question 11

How to find the central angle of a polygon

Answer 11

360/number of sides

Question 12

What is the apothem?

Answer 12

The perpendicular line from the center of the polygon to a side

Question 13

How to find the area of a regular polygon

Answer 13

A= 1/2 (apothem) (base) (# of sides)

Question 14

Steps to find Area of a polygon

Answer 14

1] 360/# of sides (find central angle)
2] Drop apothem (splits angle and base)
3] Plug in known values and solve with formula

Question 15

Area of a rhombus/kite

Answer 15

1/2 (d1 * d2)

Question 16

Difference between arc measure and arc length

Answer 16

AM- Degrees
AL- Feet, meters, etc.

Question 17

How to find the radius when you have the circumference

Answer 17

Divide the circumference by 2π

Question 18

How to find a perimeter with straight pieces and semi-circles in a polygon

Answer 18

360-known angle = New angle
New angle/360 * circum.
Multiply the top by the number of curved pieces
Add perimeter of straight pieces

Question 19

Finding the area with a fraction

Answer 19

Square both parts
π goes on top

Question 20

How to find the area of a few triangles in a circle
Pie

Answer 20

Turn shaded into a fraction
Shaded/Total triangles * Total area

Question 21

Find arc measure in a circle

Answer 21

Arc measure/360 * Area of circle

Question 22

How to find the area of an equilateral triangle

Answer 22

A= √3/4 * side²

Question 23

Radius on a regular polygon

Answer 23

The line from the center to the corner

Question 24

Find area of a square with diagonal

Answer 24

A = 1/2d²