Translate the word problem below into an equation men bove,
Lyle was a careful craftsman, but he wasn't very creative, For example, he only sold two types of
wooden benches stained and unstained. The unstained benches cost $20 each and the stained cost $32
each. If Lyle sold 21 benches last month (stained and unstained combined) and collected a total of $600,
how many unstained benches did he selle