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If |[2x,5],[8,x]|=|[6,-2],[7,3]| write the value of x.

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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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