gioanny39x 3 years ago What is the solution of log 2x – 3^125 = 3 ? x = 1 over 3 x = 1 x = 7 over 3 x = 4

1. telltoamit

log basex a = b implies x^a = b

2. gioanny39x

i dont understand

3. Wired

Is this correct? \[\Large \log (2x-3^{125}) = 3\]

4. telltoamit

nah the base is 2x - 3

5. gioanny39x

so confuse >.<

6. Wired

@telltoamit Only @gioanny39x can say that for sure. Gio, you need to confirm if I have the equation correct or not. Also, your formula is wrong. \[\Large log_B(X) = Y\] is the same as \[\Large X = B^{Y}\] Example: \[\Large log_10(1000) = 3\] B = 10 X = 1000 Y = 3 Using the 2nd form of the equation: \[\Large X = B^{Y}\] \[\Large 1000 = 10^{3}\]

7. ash2326

\[\log_{2x-3} 125=3\] Is this your question @gioanny39x ?

8. telltoamit

only this gives the answer in options lol

9. gioanny39x

|dw:1343929733059:dw|

10. Wired

Ok, so: B = 2D-3 (easier to use D to not confuse with X) X = 125 Y = 3 \[\Large X = B^{Y}\] \[\Large 125 = (2D-3)^{3}\] Solve for D. Hint: 125 is the cube of a single digit number.

11. gioanny39x

(2d-3)(2d-3)(2d-3) 4d^2-6d-6d+9 4d^2-12d+9(2d-3) 8d^3-12d^2 -24d^2+36d 28d-27 125=8d^3=36d^2+64d+27?

12. gioanny39x

@Wired

13. Wired

You're creating too much work for yourself. What is the cube root of 5? Hint: \[\Large X^{3} = (15Y+5)^{3}\] \[\Large X = (15Y+5)\] If you have two items that when cubed equal each other, the items equal each other.