Angles , Basic def. Flashcards
(20 cards)
Definition of angle
Consists of two rays in a plane with a common endpoint.
The two rays are the sides of the angle.
The common endpoint is called the vertex of the angle.
An angle is in standard position if ……
its vertex is at the origin and its initial side is along the positive
x-axis.

Quadrantal angles
Angles in standard position having their terminal sides along the x-axis or y-axis, such as angles with measures 90°, 180°, 270°, and so on.
Positive angle
The rotation of the terminal side of an angle is counter-clockwise.

Negative angle
The rotation of the terminal side is clockwise.

Acute Angle

Right angle

Obtuse angle

Straight Angle

Complementary angles
Two positive angles whith measures whose sum is 90°
Supplementary angles
Two positive angles whith measures whose sum is 180°
Conjugate angles
Two positive angles whith measures whose sum is 360°
Coterminal angles
To find an expression that will generate all angle coterminal with a given angle, add integer multiples of 360° to the given angle.
Reference angle
The positive acute angle (less than 90°) that is formed by the terminal side of the angle and the x-axis
1° =
60’ or 3600’’
Adjacent angles
Are ones that sum 180° and share a side

Alternate Interior Angles
are the ones that lie on opposite sides of transversal line and in the internal part of the parallel lines and are nonadjacent,

Alternate exterior Angles
Are those that lie on the opposite side of the transversal line and on the external part of the parallel lines and are nonadjacent .

The corresponding Angles
Are the ones that lie on the same side of the transversal line and one is on the internal side and one on the external side of the parallel lines

The vertical Angles
Are the ones that are nonadjacent, are opposite to the vertex and are one in front of the other
