Answer:
a = c + 16
Step-by-step explanation:
a = b + 12
b = c + 4
Solve for b in the first equation.
a = b + 12
a - 12 = b
Put b as a - 12 in the second equation and solve for a.
a - 12 = c + 4
a = c + 4 + 12
a = c + 16
There are 12 months in a year so. 85x12=1020
(-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