Post a New Question

Math

posted by .

solve log(7x-3)+2log(5)=2+log(x+3)

I've attempted to do this question and I ended up with log(7-3)+log(5^2)-log(x+3)=2 but I don't what to do next or whether I did something wrong.

  • Math -

    write is as

    log((7x-3)(25)/(x+3) = 2
    25(7x - 3)/(x+3) = 10^2 = 100
    divide by 25
    (7x-3)(x+3) = 4
    cross-multiply
    7x-3 = 4x+12
    3x = 15
    x = 5

    check:
    LS = log 32 + log 25 - log 8
    = log(32(25)/8)
    = log 100
    = 2
    = RS

  • Math -

    Just wondering what did you do in this log((7x-3)(25)/(x+3) = 2 to get 25(7x - 3)/(x+3) = 10^2 = 100?

Answer This Question

First Name:
School Subject:
Answer:

Related Questions

More Related Questions

Post a New Question