It’s B
If y-x=6
Y +X =_10
then y= 6 + x, instead of y insert this no
6+ x+ x =-10
6 + 2x =-10 then collect like terms
2x =-10-6
2x=-16 then multiple both side by 1/2
X=-8
Y=6+x instead of x insert -8
Y=6-8
=-2
To calculate this we simply need to devide 153 by 18.
153/18=8.5
which means that Sarah can buy 8 new CDs and will have
153 - 8*18=9 dollars spare.
Sarah has extra cash because with that spare money she can't buy whole new CD.
The slope is zero because the line is not moving