Question

help!?!? solve for x

Answer 1

Do you know the definition of log using exponents?

Answer 2

no

Answer 3

Here it is:

\(\Large \log_b x = y\) means \( \Large b^y = x\)

Now apply this to your equation. You will have a very easy to solve equation left.

Answer 4

339

Answer 5

a log function is the inverse of an exponential function.

Therefore, the inverse of \[\log_{7} (x + 4) = 3\] is \[7^3 = x + 4\]


Now isolate x

and you get, \[x = 7^3 \] solve for x

Answer 6

srry, i meant \[x = 7^3 - 4\]

Answer 7

340?

Answer 8

yes, it is 339

Answer 9

i have anther if you care to help?

Answer 10

ok, sure

Answer 11

solve for x

Answer 12

ok, so here u are dealing with natural logarithms. So the properties of natural logarithms stays the same as for logarithms.

You have, \[\ln (5x - 3) + \ln (x + 2) = \ln(5x^2 + 9)\]

Well, lets start by simplyifing the left side of the equation.

The properties of natural logarithms tells us that \[\ln(xy) = \ln(x) + \ln(y)\]

Therefore,

\[\ln[(5x - 3)(x + 2)] = \ln(5x^2 + 9)\]

Use FOIL and multiply the stuff inside the brackets.

\[\ln(5x^2 + 7x - 9) = \ln(5x^2 + 9)\]


Now, since the bases on both sides of the equation is equal, the ln cancels out leaving:

\[5x^2 + 7x - 9 = 5x^2 + 9\]


Can you solve x? Hint* use quadratic formula.

Answer 13

No need for the quadratic formula. The x^2 terms cancel out.

Answer 14

umm... okay.. i didnt see tht lol

Answer 15

7/15

Answer 16

?

Answer 17

\[7x = 5x^2 - 5x^2 + 9 + 9\]

\[7x = 18\]

solve for x

Answer 18

3/7?

Answer 19

how did u get 3/7?

Answer 20

do i multipley?

Answer 21

sorry i'm kind of lost

Answer 22

isolate x

therefore, divide both sides by 7