a) \({a^2}x + x = 2{a^4} - 2\)
\(\eqalign{ & x\left( {{a^2} + 1} \right) = 2\left( {{a^4} - 1} \right) \cr & x = {{2\left( {{a^4} - 1} \right)} \over {{a^2} + 1}} \cr& x= {{2\left( {{a^2} - 1} \right)\left( {{a^2} + 1} \right)} \over {{a^2} + 1}} \cr& x= 2\left( {{a^2} - 1} \right) \cr} \)
b) \({a^2}x + 3ax + 9 = {a^2}\)
\(\eqalign{ & ax\left( {a + 3} \right) = {a^2} - 9 \cr & x = {{{a^2} - 9} \over {a\left( {a + 3} \right)}}\cr& x = {{\left( {a - 3} \right)\left( {a + 3} \right)} \over {a\left( {a + 3} \right)}} \cr& x = {{a - 3} \over a} \;\;( a ≠ 0; a ≠ -3) \cr} \)
