SOLUTION: logx(base of x)of 9 = -2

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Question 96811: logx(base of x)of 9 = -2
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
log%28x%2C9%29=-2


9=x%5E-2 Rewrite the equation using this property: log%28b%2Cx%29=y ===> b%5Ey=x


9=1%2Fx%5E2 Flip the variable with the negative exponent


9x%5E2=1 Multiply both sides by x%5E2


x%5E2=1%2F9 Divide both sides by 9


x=0%2B-sqrt%281%2F9%29 Take the square root of both sides


So our possible answers are:

x=1%2F3 or x=-1%2F3


However, since a negative log is undefined, the only solution is


x=1%2F3