The sum of three times a number and ten is twenty two. find the number

3x + 10 = 22

to find x, first you must subtract 10 from both sides

10 - 10 = 0
22 - 10 = 12

this means 3x = 12

divide both sides by 3 to find out the value of x

3x / 3 = x
12 / 3 = 4

this means that x = 4, I hope I helped ! :)