SOLUTION: solve the equation using exact values. check for any extraneous roots. 9^2x+4(9^x)=21 Thank you

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Question 1042180: solve the equation using exact values. check for any extraneous roots.
9^2x+4(9^x)=21
Thank you
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!




Let , then



Solve for



So or

Substitute back



Not possible. Range of is









Check



John

My calculator said it, I believe it, that settles it