Given system of equations can be written in matrix form as AX=B where A=11223535a and B=69b Since, system is consistent and has infinitely many solutions ∴(adj.A)B=0 ⇒3a−2510−a−115−2aa−6−11−2169b=000⇒−6−9+b=0⇒b=15 and 6(10−a)+9(a−6)−2(b)=0⇒60−6a+9a−54−30=0⇒3a=24⇒a=8 Hence, a=8,b=15.