I just need help for these problems this morning asap if possible. :)
1.
Solve the logarithmic equation.
y=log(5) 125
Enter your answer
y =
2.
Options
3.
x=
Please and thank you!!!!!! 0^>
I don't quite understand the first one, Phoenix....are we multiplying log(5) by 125???
2.
5 * 8^(4x) = 376 divide both sides by 5
8^(4x) = 376 / 5 take the log of both sides
log 8^(4x) = log (376 / 5)
Remember that log a^b can be written as b*log (a)
So
(4x) log (8) = log (376/5)
x *(4 * log 8) = log (376 / 5) divide both sides by (4 * log 8)
x = log (376/5) / [ 4 * log 8 ] = log (75.2) / (4log 8)
Last one
The key here is to notice that 81 = 3^4
The reason for doing this is that we won't have to use any logs to solve for x
So....we actually have
3^(7x) = (3^4)^(x + 9)
Remember that (a^m)^n = a^(m * n) so.....
3^(7x) = 3^(4 * (x + 9) )
Since the bases are the same, we can solve for the exponents
7x = 4 (x + 9) simplify
7x = 4x + 36 subtract 4x from both sides
3x = 36 divide both sides by 3
x = 12
Thank you much for your help CPhill...I may have worded the first question wrong on my end. I was able to complete it okay on my own. :)