Hally
Solve the equation. Identify any extraneous solutions.
sqrt a = -8
A. –64 is a solution of the original equation. 64 is an extraneous solution.
B. 64 is a solution of the original equation.
C. 64 is a solution of the original equation. –64 is an extraneous solution.
D. no solution <<<
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tyteen4a03
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To get rid of square roots, square both sides.
precal
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|dw:1359074224200:dw|do just like tyteen4a03 suggested
Hally
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a=64?
Hally
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so, is it b or c??
Hally
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i say c. am i right??
tyteen4a03
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@Hally The answer is B. Whenever you are raising a number to an even number, the negative sign disappears. (If you need proof just ask.)
Hally
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i know that part thanks! :)
precal
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|dw:1359074648834:dw|
precal
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|dw:1359074661681:dw|question is, is this true?
Hally
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no. sqrt 64 = 8 and 8 is not equal to -8
precal
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|dw:1359074893672:dw|
precal
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then that means that the solution is extraneous
Hally
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oh. so the answer is "64 is a solution of the original equation. –64 is an extraneous solution" .... right?