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anonymous
 4 years ago
Solve for x
anonymous
 4 years ago
Solve for x

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0\[\huge (5)(8)^{(x+2)} = 5^{7x}\]

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1\[5 \dot\ 8^{x+2} = 5^{7x} \\ 5 \dot\ 8^x 8^2 = \left(5{^7}\right)^x \\5 \dot\ 8^2 = \frac{\left(5{^7}\right)^x}{8^x} \\5 \dot\ 64 = \left(\frac{5^7}{8}\right)^x \\320 = \left(\frac{5^7}{8}\right)^x \] Take logs of both sides and finish simplifying

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1359086666173:dw

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0this is what i'm getting, but it is wrong

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0wait, we're we sipposed to take the log of both sides?

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1\[\ln(320) = \ln\left(\left(\frac{5^7}{8}\right)^x\right) \\\ln(320) = x \ln\left(\frac{5^7}{8}\right) \\\frac{\ln(320)}{\ln\left(\frac{5^7}{8}\right)} = x \\\frac{\ln(320)}{\ln5^7  \ln2^3} = x \\\frac{\ln(320)}{7\ln5  3\ln2} = x\]

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1Uh, ya....logs of both sides. What you do to one side, you do to the other side.

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1The last two lines, either form, is what you want.

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1By the way, don't forget that you are isolating x bro. Don't confuse the numerator and the denominator.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0yeah i know but im getting a weird answer idk why .

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1You should have gotten what I got above. And if you're approximating, you should get x ≈ 0.628

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1You did not isolate x properly bro.

Hero
 4 years ago
Best ResponseYou've already chosen the best response.1Take a look at your second to last step.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ohhh, i figured it. i flipped it

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0got it ! thanks man :)
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