What is x in this equation?

3x + 1 = 10

If x + 10 = 70, what is x? a. 40 b. 50 c. 60 d. 70 e. 80

Hello people, i have a math question that i need with, me, i will give the correct one brainiest, and for the other correct people, a and 5 stars.

You have 3 boxes, one "strawberries"; one "mentos" and one "mixed".but you know that all the labels are in incorrect order .how do you know witch is witch?