Question

HELP, WILL REWARD!
Solve the exponential equation.
125^7x-2=150

a.-0.1375
b.2.1483
c.0.4234
d.0.4340

Answer 1

is it like this?
\[125^{(7x-2)}=150\]

Answer 2

Yes!

Answer 3

have you learned about logarithms?

Answer 4

yes i just dont get this equation

Answer 5

so take the log (or natural log) of both sides...
\[ 125^{(7x-2)}=125\Rightarrow \ln\left(125^{(7x-2)}\right)=\ln125\]\[\Rightarrow (7x-2)\ln125=\ln125 \Rightarrow 7x-2=\frac{\ln125 }{\ln125}\]
can you solve it from here?

Answer 6

oops, i mean like this \[7x-2=\frac{\ln150}{\ln125}\]

Answer 7

I got 3.74.

Answer 8

let's look...

\[7x-2=\frac{\ln150}{\ln125} \Rightarrow x=\left(2+\frac{\ln150}{\ln125}\right)\div 7=(2+1.0377609175...)\div 7=\frac{3.0377609175...}{7}\]

Answer 9

this should be less than .5.

Answer 10

i cant see the full equation that you wrote.

Answer 11

\[x=\frac{3.077609175...}{7}\]

Answer 12

0.439 is what i got but its none of the answer choices

Answer 13

i got .4339... which rounds to

Answer 14

d?

Answer 15

are you asking or telling?

Answer 16

asking?

Answer 17

k, you should be telling. the whole idea is to get confortable and then confident

Answer 18

are you unsure of any of the steps?

Answer 19

Never said i wasnt comfortable or confident so yea. Nothing wrong with asking dude.

Answer 20

I get it.

Answer 21

you're right, nothing wrong with asking. don't get me wrong, i just want you to understand how to do these. if you're asking if something is right then my feeling is that you're unsure of something, that's all. and i want to know where that's occurring so i can do my best to help you with that.