To simplify the expression 3(y + 4) + (2y - 5) - 1(y - 2), we can apply the distributive property and combine like terms:
3(y + 4) + (2y - 5) - 1(y - 2)
= 3y + 12 + 2y - 5 - y + 2 (distributing the 3, 1, and -1)
= (3y + 2y - y) + (12 - 5 + 2) (combining like terms)
= 4y + 9 (simplifying further)
Therefore, the simplified expression is 4y + 9.