The error is in the second step they subtracted 3 from both sides but it was a 3x, which you can not do.
Correction.
9x+18+3x=1
12x+18=1
12x=-17
x=-17/12
Answer:
No they or not
Step-by-step explanation:
The first on is 60 and the second one is 40
It would be D:7
It needs to have one side bigger than