Factor out common term: Simplify the expression by factoring out the greatest common factor.18u+9= 9(2u+1)
Check for divisibility: Check if 2 is a factor of the simplified expression 9(2u+1).Since 9 is not divisible by 2 and 2u+1 is an expression where 2 is a factor of 2u but not of the +1, 2 is not a factor of the entire expression 9(2u+1).