Answers:
∠6 = 50°
∠8 = 40°
∠9 = 140°
Step-by-step explanation:
∠6 & 130°... supplementary angles, which means they must add up to 180°
∠8 & 40°... vertical angles, which means that they are equal in value... and...
∠9 & 40°... also supplementary angles