The standard from of a line has both variables on one side of the equal sign and a constant on the other side. (by convention is should be arranged so that the coefficient of x is positive)
y-3=3(x+1) perform indicated multiplication on right side
The first thing you do is convert the oz into pounds. There is 16 oz in a pound so our fraction is 9/16 which is 0.5625 . Then adding to the pounds it becomes 6.5625 pounds. Then multiply by 1.3.