Mathitat
Serious maths,
gently done.

Co-interior angles

Practise this

Angles between two parallel lines that add up to 180° (C-shape).

In Español · sample
Ángulos conjugados internosÁngulos entre dos rectas paralelas que suman 180° (forma de C).

Angle ___ = 180° − ___° = ___° because co-interior angles on parallel lines add up to 180°.

Angle x = 180° − 120° = 60° because co-interior angles on parallel lines add up to 180°.