Question 214785
( x+6)^1/2 = (x-9),,,,,,square  both  sides
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(x+6) = (x^2 -18x +81)
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0 = x^2 -19x +75,,,,solve  by  quadratic  formula
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a=1,,,,b=-19,,,,,c=75
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x=[ -(-19) +/- sqrt{ (-19)^2 - 4 (1)(75)} ] /2(1)
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x=[ 19 +/- sqrt{ 361 - -300)}] 2
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x= [ 19 +/- 7.810] /2
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x= 13.405,,5.595
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check,,,(5.595),,,,,,( 5.595 +6)^1/2 = 5.595 -9 = -3.405
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+/-3.405 =-3.405,,,,ok
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(13.405),,,,,,(13.405 +6)^1/2 = 13.405 -9 = 4.405
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+/-  4.405 = 4.405,,,,,,,,ok
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