Angle Relationships
Ever notice how angles work together in shapes? There are four key relationships you need to know. Let's break them down!
Complementary angles add up to exactly 90 degrees. Think of them as "friends" that complete a right angle together. For example, if angle x is 30° and angle y is 60°, they're complementary because 30° + 60° = 90°.
Supplementary angles add up to 180 degrees - a straight line. When two angles are supplements of each other, they form a straight line when placed together. If angle x is 45° and angle y is 135°, they're supplementary because 45° + 135° = 180°.
Adjacent angles share both a common vertex (corner point) and a common side, but don't overlap. They sit right next to each other like neighbors. If you have angle x next to angle y, they form a larger angle z where x + y = z.
Remember this! Vertical angles are formed when two lines cross each other. They're the opposite pairs that don't touch but are always equal in measure. This is one of geometry's most useful relationships - these angles are always congruent (equal) no matter what!