What is this pill -light blue with M47 on one side and a slash mark on backside?

Pill imprint M 47 has been identified as Metoprolol tartrate 100 mg.

Metoprolol is used in the treatment of atrial fibrillation; high blood pressure; supraventricular tachycardia; benign essential tremor; premature ventricular depolarizations (and more), and belongs to the drug class cardioselective beta blockers.

Pill image: https://www.drugs.com/imprints/m-47-359.html