11^х+2*11^(х-1) = 143
11*11^(х-1)+2*11^(х-1) = 143
11^(х-1)*(11+2) = 13 * 11
13*11^(x-1) = 13*11
11^(x - 1) = 11
x - 1 = 1
x = 2
11^х+2*11^(х-1) = 143
11*11^(х-1)+2*11^(х-1) = 143
11^(х-1)*(11+2) = 13 * 11
13*11^(x-1) = 13*11
11^(x - 1) = 11
x - 1 = 1
x = 2