Question

solve it please plz plz

Answer 1

Answer:

${5}^{x} + {5}^{ x - 1} = 750 \\ {5}^{x} + {5}^{x} \times {5}^{ - 1} = 750 \\ {5}^{x} (1 + \frac{1}{5} ) = 750 \\ {5}^{x} \times \frac{6}{5} = 750 \\ {5}^{x} = 750 \times \frac{5}{6} = 125 \times 5 = 625 \\ {5}^{x} = {5}^{4} \\ x = 4$