Could I have some help with extraneous problems, please?
@jdoe0001 @johnweldon1993
Mr. Jones is asked to write two types of radical equations for the SAT Prep Course. The first solution to the radical equation must be extraneous. The second solution to the radical equation must be non-extraneous. Write one equation where the solution is extraneous. Then write a second equation where the solution is non-extraneous.
Hmm...if I gave you the equation \[\large \sqrt{x} = x - 6\] solve that for me :)
First step? Square both sides right? \[\large \sqrt{x}^2 = (x - 6)^2\] \[\large x = (x - 6)^2\] Second step? expand that right side out \[\large x = x^2 - 12x + 36\] Third? Subtract x from both sides of the equation \[\large x^2 - 13x + 36 = 0\] can you solve that quadratic for me? should get 2 easy answers if I did it right :)
Oh sorry! Does x=9?
That's 1 answer....what about the second? :)
4?
Perfect..so if x = 9 and x = 4 Lets check to make sure they both work If we check 9.. \[\large \sqrt{x} = x -6\] \[\large \sqrt{9} = 9 -6\] \[\large 3 = 3\] So that works..check 4 for me :)
2=-2
Ohh looky there...it doesnt work out...thus we have...and extraneous solution :)
Fabulous! How about a non extraneous solution?
Well a non extraneous ...hmm try \[\large \sqrt{x - 2} = 5\]
x=27!
Mmhmm :) and that's the ONLY solution...no extraneous thing trying to confuse us >.< lol :P
Okay, got it. Thanks again! Really appreciate you OpenStudy people!
Lol no problem :P it's what we're here for :)
Would you mind helping me with one last problem?
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