How do you solve 3^x+1=243 ?

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Answer 1 · 2017-12-28T22:13:56

See below.

Not sure whether this is $3^(x+1)=243$ or $3^x+1=243$
$3^x+1=243$ is what is written, but I'm suspecting it's supposed to be $3^(x+1)=243$

$3^(x+1)=243$

Taking logs of both sides:

$(x+1)ln(3)=ln(243)$

$x+1=ln(243)/ln(3)$

$x=ln(243)/ln(3)-1=ln(3^5)/ln(3)-1=(5ln(3))/ln(3)-1=4$

Answer 2 · 2018-08-05T02:42:45

$x=4$

We have the following:

$3^(x+1)=243$

We can rewrite $243$ as $3^5$ . We now have

$3^(x+1)=3^5$

Since we have the same base, we can equate the exponents. We get

$x+1=5$ , which easily solves to

$x=4$

Hope this helps!