Angle Relationships

bloco de notas

The amount of space between two straight lines that have a common end point is called angle. Two angles can be related if certain conditions are met. Here, we will learn how to identify these kind of angles and use the correct term to describe them.

NameImageDescription
Vertical AnglesVertical AnglesThe angles opposite each other when two lines cross. In the figure, the 1 and 3 are vertically opposite angles and they are always equals. Same goes for angles 2 and 4.
Corresponding AnglesCorresponding AnglesThe angles in matching corners when two lines are crossed by another line, called the transversal. One is internal and the other external. They are equals if the two intersected lines by the transversal are parallel. In the figure, angles 1 and 2 are corresponding. The 1 is external and the 2 is internal.
Alternate Exterior AnglesAlternate Exterior AnglesAngles that are on opposite sides of the transversal of two other lines. Both are external. They are equals if the two intersected lines by the transversal are parallel. In the figure, angles 1 and 4 are alternate exterior angles.
Alternate Interior AnglesAlternate Interior AnglesAngles that are on opposite sides of the transversal of two other lines. Both are internal. They are equals if the two intersected lines by the transversal are parallel. In the figure, angles 2 and 3 are alternate interior angles.
Adjacent AnglesAdjacent AnglesTwo angles which share a common vertex and side, but have no common interior points. In the figure, the `alpha` and `beta` are adjacent angles.
Complementary AnglesComplementary AnglesTwo angles are called complementary when their sum is 90º. In the figure, the `alpha` and `beta` angles together form a right angle.
Supplementary AnglesSupplementary AnglesTwo angles are called supplementary when their sum is 180º. In the figure, the `alpha` and `beta` angles together form a straight angle.


escrever carta

If you have any pertinent (math) question and you are not able to easily find a answer, then send us a message through the Contact page. We will be happy to respond. In the event that you detect any errors in our summary tables, do not hesitate to let us know! We will try to correct it as soon as possible.