# Math Help - Help with logarithms!

1. ## Help with logarithms!

Please help me figure out how to solve the following:

1) 4^(x+2) = 16^(2x-2)

2) log SUB 3(5x+1) = 4

3) 4^(4x+1) = 8^(3x)

Thanks in advance!

2. Originally Posted by kcwillia377
Please help me figure out how to solve the following:

1) 4^(x+2) = 16^(2x-2)

note that $4^2 = 16$

2) log SUB 3(5x+1) = 4

change to an exponential equation ... $3^4 = 5x+1$

3) 4^(4x+1) = 8^(3x)

note that $8 = 2^3$ and $4 = 2^2$
.

3. 1) $log(4^{x+2})=log(16^{2x-2})$

$(x+2)log(2^{2})=(2x-2)log(2^{4})$

$(2x+4)log(2)=(8x-8)log(2)$

$2x+4=8x-8$

$12=6x$

$x=2$

2) $3^{4}=5x+1$

$80=5x$

$x=16$

3) $log(4^{4x+1})=log(8^{3x})$

$(4x+1)log(2^{2})=(3x)log(2^{3})$

$(8x+2)log(2)=(9x)log(2)$

$8x+2=9x$

$x=2$