6x+2y=12 ( solve for y )
How do I show my work on a piece of paper would help a lot :)

Leo has b boxes of pencils. each box contains 6 pencils. he has a total of 42 pencils. the equation that represents this situation the value of b that makes the equation true the first one is b+6=42,6b=42,b=42+6,or 42b=6 the second one are 7,836 48

The graph represents the gallons of water in a water tank with respect to the number of hours since it was completely filled

Three times the sum of a number and seven is negative thirty-six. what is the number?