When Marcus was 6 years old, his dad planted a 7 foot maple tree. They can grow up to 2 feet per year. The tree is now 25 feet tall. How many years ago did his dad plant the tree

He Planted 9 yrs ago.

So we know that Marcus was 6 when they planted a 7 foot maple tree (how do they even "plant" that thing?), and it grows 2 feet per year.

So that means it grew 25-7 = 18 feet.

18 / 2 = 9.

So that means it grew 18 feet in 9 years.

That means that Marcus's dad planted the tree 9 years ago.