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The centroid of an equilateral $$\triangle$$XYZ is L. If XY = 12 cm, then the length of XL (in cm), is:
In the equilateral traingle XYZ, XY = 12 cm
$$\Rightarrow$$ YZ = XZ = 12 cm
The median XP bisects YZ at P and also perpendicular to YZ in the equilateral triangle.
$$\Rightarrow$$ YP = PZ = 6 cm and XP$$\bot\ $$YZ
The centroid L divides the median XP in the ratio of 2 : 1
$$\Rightarrow$$ XL : PL = 2 : 1
$$\Rightarrow$$ XL = 2PL .............(1)
In $$\triangle$$XPZ,
XP$$^2$$ + PZ$$^2$$ = XZ$$^2$$
$$\Rightarrow$$ XP$$^2$$ + 6$$^2$$ = 12$$^2$$
$$\Rightarrow$$ XP$$^2$$ + 36 = 144
$$\Rightarrow$$ XP$$^2$$ = 108
$$\Rightarrow$$ XP = $$6\sqrt{3}$$
$$\Rightarrow$$ XL + PL = $$6\sqrt{3}$$
$$\Rightarrow$$ 2PL + PL = $$6\sqrt{3}$$
$$\Rightarrow$$ 3PL = $$6\sqrt{3}$$
$$\Rightarrow$$ PL = $$2\sqrt{3}$$
$$\Rightarrow$$ XL = 2PL = $$4\sqrt{3}$$
Hence, the correct answer is Option C
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