Consider number 17. You know that
17=9+8.
Then for negative numbers you have the same rule (with respect to sign -):
-17=(-9)+(-8).
Since (-9)+9=9+(-9)=9-9=0, you have that
-17+9=(-9)+(-8)+9=(-9+9)+(-8)=0+(-8)=-8.
Answer: -17=(-9)+(-8).
Step-by-step explanation:
9 miles per day
8 days hiking
9m x 8d = 72 miles long
(-y+5x3)+(7.2y-9)=6.2y+n
(-y+15)+(7.2y-9)=6.2y+n
since you're adding the two parentheses, you don't need to have them there
-y+15+7.2y-9=6.2y+n
7.2y-y +15-9 =6.2y+n
6.2y + 6 =6.2y+n
6.2y - 6.2y -n = -6
-n=-6
n=6
