Question 195025
sqrt  ( 9x  +378 )  = 3 * sqrt ( 7x)
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squaring  both  sides
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9x+378 =9*7x=63x
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simply
.378  =  54x
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x = 7,,,,,,,ANSWER
,
checking
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sqrt ( 9*7 +378 )  =  3 * sqrt ( 7 * 7 )
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sqrt  ( 63 +378 )  =  3 *sq rt  (49)
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sqrt ( 441)  =  3 * 7
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21  =  21
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The  solution  is  ,,,,,, x = 7