2/7 = 0.29 ---- rounded up plus the 7 = 7.29
(-2 3/7) 3/7 = 0.43 ---rounded up ---- plus the -2 = -2.43
7.29 - (- 2.43) = 9.72 ----- negative and negative equal posirive
#18
-2.45 - (-3.94) = 1.49
82+82+82 is the awnser you'll be needing : )
The subtraction sign in front of the second set of parenthesis changes the signs on the terms inside those parenthesis. So this could be rewritten as

. None of the exponents on the x are the same, so we will just express it in terms of descending powers of x.

. This is also the same as

if you don't like to start with a negative. Either one is correct.