For this question the FOIL method can be used. FOIL stands for first, outside, inside, and last, and is used to make sure each term is multiplied by each other term. Firstly, multiply the first terms of each bracket:
2x x 4x = 8x2
Next multiply the outside terms of the brackets:
2x x 6 = 12x
Next multiply the inside terms of the brackets:
-2 x 4x = -8x
Next muliply the last terms of the two brackets:
-2 x 6 = -12
The result of each calculation should then put together:
8x2 + 12x - 8x - 12
Finally, the x terms can be simplified to get the final answer:
8x2 + 4x - 12