Idont know how to find the orthocenter

O = (3,3)

Explanation:

The altitude of a triangle is the perpendicular from a vertex to the opposite side.

The orthocentre (O) of a triangle is the point where the three vertices intersect.

We must find the equations for only two of the altitudes, because the third will also intersect at that point.

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Your three points make a right triangle.

The altitude of B is side AC.

The altitude of C is sde AB.

Their point of intersection at A (3,3) is the orthocentre of thetriangle.