Geometryhard · Past Paper
If a circle passes through the vertices of a triangle with sides 3, 4, and 5, what is the radius of the circle?
A2
B2.5
C5
D1.5
✓ Correct Answer: B — 2.5
The triangle is right-angled (3^2+4^2=5^2). The hypotenuse is the diameter. Radius = 5/2 = 2.5.
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