Chapter 12's Top 10 Concepts

To Find...

• Sum of Interior Angles = (n - 2)180
• Each Individual Exterior Angle = 360 / n ((n = number of sides))
• Each Individual Interior Angle = {(n - 2)180} / n ((n = number of sides))

In a Circle, You Could Find...

• Arc Length = { (measure of the arc)/360 } * (2ðr) (( * = multiply, times and ð = pi, approximately 3.14))
• Area of a Sector ((part of a circle, looks like a slice of pie)) = { (measure of the arc) / 360) } * (ðr²) (( * and ð =the same as stated above, r = radius ))
• The Great Circle - a circle formed from a plane through the center of a sphere; divides the spheres into hemispheres

In a Polyhedron, You Could Find...

• Surface Area of a Right Prism = 2B + Ph (( B = area of the base, P = perimeter of the base, h = height of the the prism))
• Surface Area of a Right Cylinder = 2B + Ph (( B = the area of a circle, 2*pi*radius, squared, P = circumference of the circle, pi*diameter, h = the height of the cylinder))
• ...or if you want to make it easier, SA = 2*pi*radius, squared + 2*pi*radius*height
• Volume of a Right Prism = Bh (( B = area of the base, h = height of the prism))
• ****if it is REGULAR, that means that the vertex is lined up at the center of the base!!!!