The answer to the expression is 2a+2b. You get the answer by first removing the brackets. To do this you need to multiply both the unlike terms with 2. Since it can't be simplified further the answer is left at 2a+2b.
2a+2b you get this by using the distributive property. To use the Distributive property you take the number outside of the parentheses, and multiply it by the first number/letter inside the parentheses. you do the same thing to the second letter/number inside. then you make an expression and or equation with it so it be 2a+2b. You cant simplify it so that is your final answer