Question

3в степени х+1 минус 4*3 в степени х-2 =69

Answer 1

$3^{x+1}-4*3^{x-2}=69 \\ 3^{x}(3-4*3^{-2})=69 \\ 3^{x}*2 \frac{5}{9} =69 \\ 3^{x}=69:2 \frac{5}{9} \\ 3^{x}=27 \\ 3^{x}=3^{3} \\ x=3 \\$

Answer 2

$3 ^{x+1} -4*3 ^{x-2} =69\\ 3 ^{x} *3 ^{1}- \frac{4*3 ^{x} }{ 3^{2} } =69/*9\\9*3 ^{x} *3 ^{1}- 4*3 ^{x} =69 *9 \\ 27*3 ^{x} -4*3 ^{x} =621\\3 ^{x} =t \\ 27*t-4*t=621\\27t-4t=621\\23t=621\\t=27\\3 ^{x} =27\\3 ^{x} =3 ^{3} \\x=3$