Question

Sabendo que 81^x + 3 = 27^x+1, qual será o valor de x^2?

Answer 1

${81}^{x} + 3 = {27}^{x + 1} \\ ({ {3}^{4} })^{x} + 3 = ({ {3}^{3}) }^{x} \times {3}^{3} \\ {3}^{4x} + 3 {}^{1} = {3}^{3x + 3} \\ 4x + 1 = 3x + 3 \\ x = 2 \\ {x}^{2} = 4$