Answer:

Step-by-step explanation:
18=9×2
27=3*9
36=4*9
45=5*9
9 and 3 are the only common factors between 54 and 90
3+4x=15
4x=15-3
4x=12
x=12/4
x=3
The check is:
<span>If x=3 then, </span>
3+ (4 X 3)=15
<span>3+12=15</span>
To isolate b, add a and subtract c to the entire equation:
D - a + c = -b
Muliply b by -1 to eliminate the negative:
-D + a - c = b
Answer:

Step-by-step explanation:
As an improper fraction