2aa+a

Assuming the expression is 2a^2 + a (i.e., 2a·a + a):

• Factor out the greatest common factor a: a(2a + 1)
• Check: a(2a + 1) = 2a^2 + a

If you want to solve 2a^2 + a = 0, the solutions are a = 0 or a = -1/2.