Question

2^n-7*5^n-4=1250
pls tell the answer​

Answer 1

${2}^{n - 7} \times {5}^{n - 4} = 2 \times {5}^{4} \\ now \: \\ {2}^{n - 7} = 2 \: \: and \: \: {5}^{n - 4} = {5}^{4} \\ n - 7 = 1 \\ n = 8 \\ or \: \\ {5}^{n - 4} = {5}^{4} \\ n - 4 = 4 \\ n = 8$