In the first group (1--7), check 5 and 6. In the second, group, unfortunately, all are wrong. For example, (x + 12)^2 = x^2 + 24x + 144.
You can check such calculations online at WolframAlpha. Just type (x + 12)^2, press Enter, and look for Alternate forms. But remember that with great power come great responsibility. I mean that if you are ever going to need to solve these problems by hand, you most certainly must train hard in doing this by hand.