10a+b-10b+a=a(b-1)⇒11a-9b=ab-a⇒12a=ab+9b
a ≠ b
a≠0
a=1⇒12=b+9b⇒12=10 b,nu verifica
a=2⇒24=2b+9b⇒24=11 b,nu verifica
a=3⇒36=3b+9b⇒36=12b⇒b=3,nu verifica deoarece a≠b
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a=9⇒108=18b⇒b=6
Deci a=9 si b=8