The answer is b because of the letter in the answer.
Is it a because if you take 3 away for 10y that equals 7y and then you plus the 5
The three points form a right triangle with legs length 3in and 4in. So, the area is

So, both sides of the pillow will require 12 squared inches.
5.
there are 180 degrees in any triangle and 105 is more than half of 180 so 105 is obviously the biggest then DCE looks bigger than CDE so the order from smallest to bigest is CDE,DCE, CED
6. 180 degrees in any triangle so the right angle is 1/2 of that so it's the biggest angle
side HI has a legth of 4 while side GI has a side legnth of 6 so angle GHI is bigger than angle IGH so the order from smallest to biggest is IGH, GHI, GIH