X+ (x+1) + (x+2) =135 is the way you would write the expression, x being the smallest number. Simplify the side of the equation with the variables so that its 3x + 3=135. Next, subtract 3 on both sides so that 3x=132. Next, isolate x by dividing both sides by 3 so that x=44. Check your work by substituting 44 in for x so that 44+45+46=135.
