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Log5 (x squared - 9) = 0

User MandisaW
by
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1 Answer

10 votes

Answer:


x=3,\:x=-3

Explanation:

Given the equation


\log _(10)\left(5\right)\left(x^2-9\right)=0

Divide both sides by
\log _(10)\left(5\right)


(\log _(10)\left(5\right)\left(x^2-9\right))/(\log _(10)\left(5\right))=(0)/(\log _(10)\left(5\right))

Simplify


x^2-9=0

Add 9 to both sides


x^2-9+9=0+9

Simplifying


x^2=9


\mathrm{For\:}x^2=f\left(a\right)\mathrm{\:the\:solutions\:are\:}x=√(f\left(a\right)),\:\:-√(f\left(a\right))


x=√(9),\:x=-√(9)

as


√(9)\:=3


-√(9)=-3

Therefore,


x=3,\:x=-3

User Kaykun
by
5.2k points