Question

Let A, B, C are the points on x, y and z axes respectively in a three dimensional co-ordinate system with O as origin. Suppose the area of triangles OAB, OBC and OCA are 4, 12 and 6 respectively, then the area of the triangle ABC equals

• A. 16
• B. 14
• C. 28
• D. 32

Answer 1

The correct option is B 14

$\left[ABC\right]=\sqrt{[OAB{]}^2+[OBC{]}^2+[OCA{]}^2}$
where [ABC] = area of triangle ABC