She earns ($9.70x40) for a 40 hour week=$388
She earned $489.85-$388 extra= $101.85
She gets paid $9.7x1.5 for every extra hour=$14.55
She worked $101.85/$14.55 hours extra=7hours
She worked 7+40 hours that week=47 hours
The first thing to do with these problems is to convert them into y=mx+b form; this will literally show you the answer to slope and y intercept since m=slope and b=y intercept.
To convert, isolate the y and the rest should fall into place. Subtract 2x from 4y and the other side of the equation to get the equation 4y= -2x+9 (put the x first because of mx+b). Then Divide the 4 from y and do the same to the other side to get y= -1/2x+9/4. M= -1/2 so that is the slope. B=9/4 so that is the y intercept
Divide: 7/3: 1/5= 7/3· 5/1= 7 · 5/3 · 1= 35/3
The answer to your question is composite and the factors are 1,2,3,4,6,9,12,18,36