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Question
If `|[2x,5],[8,x]|=|[6,-2],[7,3]|`, write the value of x.
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Solution
We have:
`|[2x,5],[8,x]|=|[6,-2],[7,3]|`
`⇒2x^2−40=18+14`
`⇒2x^2=32+40`
`⇒2x^2=72`
`⇒x^2=36`
`∴ x=±6`
Thus, the value of x is ±6.
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