Question 303639
x=sqrt(3x+40)
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Square both sides to get:
x^2 = 3x+40
Rearrange:
x^2 - 3x - 40 = 0
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x^2-8x+5x-40 = 0
x(x-8)+5(x-8) = 0
(x-8)(x+5) = 0
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x = 8 or x = -5
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Checking:
8 = sqrt(24+40)
8 = sqrt(64)
true
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-5 = sqrt(-15+40)
false
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Only solution: x = 8
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Cheers,
Stan H.