After consideration I'm not sure but I think x=3 and y=6 I'm not a math whiz but this made sense to me.
Subtract 79 from both sides to isolate variable b.
b = 159 - 79
b = 80
Answer:
$20
Step-by-step explanation:
5 copies cost $1.
25 copies cost $5.
So you have to do 100/5=$20 for 100 copies.
