Solve the following: \text { (i) } 12 x+17=65 14 x-13 y=16 \text { (iii) } 5 x^{2}+7 x-19=0 ) Find the sum to infinity for the series 18+ 12

+ 8+ …. Determine the values of a, b, c and d: (1+2 x)^{a}=1+b x+24 x^{c}+d x^{3}+16 x^{4}