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Question
Find the value of x, if `|(2,4),(5,1)|=|(2x, 4), (6,x)|`.
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Solution
`|(2,4),(5,1)|=|(2x, 4), (6,x)|`
⇒ 2 × 1 − 5 × 4 = 2x × x − 6 × 4
⇒ 2 − 20 = 2x2 − 24
⇒ −18 = 2x2 − 24
⇒ 2x2 − 24 + 18
⇒ 2x2 − 6
⇒ 2x2 = 6
⇒ `x^2 = 6/2`
⇒ x2 = 3
⇒ x = `± sqrt3`
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