Y+23=59

solve for y i dont know if i have to add or subtract the 23 and 59

When you move a number to the opposite side of the equation, in this occasion it will be 23- it changes to the opposite value. So us 23 is a positive value you can move it and change it to a negative. Or in other words suntract -23 from all sides of the equation, which will be equal to: 
y = 59 - 23
Y = 36