# Math

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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?

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