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Ratio Given :
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AB : AC = 1 : 2
⇒ 2(3x - 4) = 2x + 12
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Solve for x :
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2(3x - 4) = 2x + 12
6x - 8 = 2x + 12
4x = 20
x = 5
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Find AC:
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AC = 2x + 12
AC = 2(5) + 12
AC = 22
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Find BC:
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BC = 7x - 2
BC = 7(5) - 2
BC = 33
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Find ratio :
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AC : BC
22 : 33
(÷11) (÷11)
2 : 3
Ratio of AC : BC = 2 : 3 (Shown)