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I don't remember the exact numbers, but I came across this projectile motion problem while doing homework and I thought the solution in the solutions manual was wrong, but my teacher assured me it is correct.

The problem goes like this:

While standing on top of a building, you launch a brick in a direction theta above the horizontal. The flight time is 3 seconds. How high is thebuilding?

I bolded building for emphasis.

The solution's manual says you can simply plug in the given values to y=voyt-1/2gt^2 and the answer, y, is the height of the building.

To me it seems like the y in that equation would be the max height that the brick reaches above the ground, which is taller than the building itself.

I asked my teacher about it and he said "The equation accounts for the additional height. It is a very common mistake for students to think that they need to break this problem up into two parts, the height of the projectile, and the height of the building"

I'm still confident that I am right in thinking that you need to find the time that the brick spends above the building, subtract that time from 3seconds (given as the total flight time), then use that time in the equation y=voyt-1/2gt^2.

If I'm wrong, can someone explain what I am missing?