7th Grade · Geometry

Vertical Angles

7.G.B.5

Definition

The pair of non-adjacent angles formed when two lines intersect. Vertical angles are always congruent (equal in measure).

Teach it

Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.

Examples

  • If ∠1 = 65°, then ∠3 (its vertical angle) = 65° too.
  • ∠2 = 180° - 65° = 115° (linear pair with ∠1).

Key rule

Vertical angles are formed across from each other at an intersection and are always equal.

Memory hook

Angles across the X from each other match.