Plane geometry question #2 - centres in a triangle

Question

callisto · Answer

I'm useless, sorry

anonymous · Answer

Orthoscenter is and intersection of the three altitudes of a triangle. To find it first find a line equation of each of the sides of the triangle and their respective perpendicular line pasing thru the respective vertice. Then just find their intersection point....

callisto · Answer

Good answer, but how can I find the equation the altitudes? I know one of them is x=18..
Sorry, I'm useless..

anonymous · Answer

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To find equation of for ex. up right  side find the slope:
(0-18)/(48-24)=-18/24=-3/4
so equation of line is (y-18) =-3/4(x-24)
The perpendicular to this one passing thru the point (0,0):
(y-0)=4/3(x-0)
Do the same for the rest