the base angles of a trapezium ABCD measures 110⁰ and 120^o.find the other 2 angles.

Let the base angle of trapezium ABCD be ∠C  and ∠D where ∠C = 110° and ∠D = 120°.

We know that , adjacent angles of a trapezium are supplementary or equal to 180°, i.e., 

∠A +∠C = 180° and ∠B +∠D = 180°

⇒ ∠A +110° = 180° and ∠B +120° = 180°

⇒ ∠A = 70° and ∠B = 60°