HURRY ILL GIVE BRAINLIEST!!

Answer:
5 + 6
Step-by-step explanation:
1: Simplify 5 + 3x, which is 5 + 6
2: He was wrong. he got 16 when the answer is 11. He could have just added 5 to 6 and gotten the right answer, while from the looks of it he used multiplication and had some bad math.