radius 14 videos

Surface Area of Spheres
Geometry Volume
How to calculate the surface area of a sphere given a radius.
sphere surface area radius 
Radii to Tangents
Geometry Circles
How to define a tangent line; how to determine the angle a radius to a tangent forms.
tangent radius right angle point outside the circle perpendicular 
Area of Circles
Geometry Area
How to derive the formula to calculate the area of a circle.
circle radius circumference area 
Regions Between Circles and Squares
Geometry Area
How to calculate the area between a square and an inscribed circle.
shaded region square circle radius 
Equation of a Circle
Geometry Pythagorean Theorem
How to derive the equation for a circle using the distance formula.
distance formula radius center circle 
Circumscribed and Inscribed Circles and Polygons
Geometry Constructions
How to define circumscribed and inscribed circles and polygons relative to each other.
vertex radius polygon inscribed circle circumscribed 
Circumference
Geometry Circles
How to calculate the circumference of a circle.
circumference pi distance radius diameter ratio 
Volume of Cones
Geometry Volume
How to compare the volume of a cone and a cylinder and how to calculate the volume of a cone given the radius and height.
volume base area height circle area 
Arc Length
Geometry Circles
How to define arc length and how it is different from arc measure; how to calculate the length of an arc.
arc length arc measure concentric circles fraction circumference radius diameter 
Area of a Sector
Geometry Area
How to derive the formula to calculate the area of a sector in a circle.
sector central angle intercepted arc circle radius area 
Area of a Segment
Geometry Area
How to derive the area of a segment formula.
segment sector triangle area radius central angle shaded area 
Parts of a Circle
Geometry Geometry Building Blocks
How to define a circle and identify its main parts.
center chord diameter radius congruent circles concentric circles arc minor arc major arc semicircle central angle