Step-by-step explanation:
s for small stones
l for large
4s+6l<=30 (<= means less or equal to because I couldn't get the sign on here).
s+l>=4. (>= means greater than or equal to).
Possible Answers:
s+l=5 (if she bought 5 stones in total)
answer #1: 5 large stones and 0 small stones.
s+l=6 (if she bought 6 stones in total)
answer #2: 3 large stones and 3 small stones.
so sorry i couldn't do the graphing part...