If triangle ABC has a 130 degrees angle at vertex cap b , which statement must be true?

The angles inside a triangle add up to 180°. Since angle B is 130°, angles A and C together must measure 180° − 130° = 50°. Therefore, the statement that m∠A + m∠C equals 50° must be true; their individual measures are not determined.

AI-written and checked against the verified answer.