Will give brainliest. Explain in detail, please and thank you.

You went to lunch with your friend, and the bill was $19.00. Your lunch is $3.00 more than your friend's. How much was your friend's lunch?

f+ 3 = 19; $8.00
3f + 2 = 19; $8.00
2 + 3 = 19; $8.00
2 - 3 = 19; $8.00