Geometry (Terms) Flashcards
Right Triangle
A Triangle with a “right” or 90° angle.
Hypoteneus
The longest side of a right triangle, opposite the right angle.
Sine (Definition)
The trigonometric function that is equal to the ratio of the side Opposite an acute angle (In a right triangle) to the Hypotenuse.
“SOH”
*Use this equation if the side is far away from the angle
Cosine (Definition)
The trigonometric function that is equal to the ratio of the side Adjacent to an acute angle (in a right triangle) to the Hypotenuse.
“CAH”
*Use this equation if the side is close to the angle
Tangent (Definition)
The trigonometric function that is equal to the ratio of the side Opposite to an acute angle (in a right triangle) to the Adjacent.
“TOA”
Circle
The locus of all points equidistant from a central point.
Tangent
A straight line or plane that just touches a curve at one point.
Secant
A line that intersects the curve in at least two (Distinct) points.
Chord
A line segment connecting two points on a curve.
Minor Arc
An arc of a circle whose measure is less than 180°.
*Usually represented by only two letters “Arc (AB)”
Major Arc
An arc of a circle whose measure is greater than 180°.
*Usually represented by three letters “Arc (ABC)”
Radius
A straight line from the center to the circumference of a circle or sphere.
Diameter
Any straight line segment that passes through the center of the circle and whose endpoints lie on the circle.
Circumference
The distance around a circle.
π (PI)
The ratio of the Circumference of a circle to its Diameter (3.142)
Arc Measure
The measure of the central angle that intercepts an arc, measured in degrees.
Arc Length
A portion of the circumference of the circle.
Degree
A unit of measurement of angles, equal to 1/360 of the circumference of a circle.
Radian
Describes the plane angle subtended by a circular arc as the length of the arc divided by the radius of the arc.
Inscribed Angle
The angle subtended at a point on the circle by two given points on a circle.
