Answer:
a)-4x+7=9×3
-4x=27-7
x=-20/4
x=-5
b)49r-55r=-52+10
-6r=-42
r=-42/6
r=7
c)-6m+8m-2m=-1-5+6
2m-2m=0
0=0
Step-by-step explanation:
6 dollars
10=1 dollar
5 dozen = 60
60 divided by 10 is 6