Coordinate Geometry
Triangle sides given; circumcentre at vertex; inradius
MMTS_Full_Test_11
Grade 12
Question:
Two sides of a triangle are $3x+4y-24=0$ and $2x+y-16=0$. Circumcentre is at $(0,6)$. Find the inradius.
(A) $6\sqrt{5}$
(B) $6(\sqrt{5}-1)$
(C) $6\sqrt{5}-10$
(D) 10
Step-by-Step Solution
Key Concept: Find the third vertex from the circumcentre condition, then compute inradius $r=\Delta/s$.
$r=6\sqrt5-10$.
Correct Answer: (C) $6\sqrt{5}-10$