Three circles of radii 4 cm, 6 cm and 8 cm touch each other

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Three circles of radii 4 cm, 6 cm and 8 cm touch each other pairwise externally. The area of the triangle formed, by the line-segments joining-the centres of the three circles is

Using Rule 1,

AB = 4 + 6 = 10 cm
BC = 6 + 8 = 14 cm
CA = 8 + 4 = 12 cm

∴ Semi-perimeter =	10 + 14 + 12	= 18 cm
	2

Area = √s(s - a)(s - b)(S - c)
= √18(18 - 10)(18 - 14)(18 - 12)
= √18 × 8 × 4 × 6
= 3 × 2 × 2 × 2√6
= 24√6 sq.cm.