Quadratic equations with word problems

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Find the two-digit number such that its ones digit is one bigger than its tens digit, and the product of the desired number and the sum of digits is $616$. Answer is $56$.

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Say the tens digit is $A$, so the ones digit is $A+1$.

Then the number is $10A+(A+1)$, and the sum of digits is $A+(A+1)$.

You want $(10A+(A+1))(A+(A+1))=616$.

That's $(11A+1)(2A+1)=616$.

Equivalently, $22A^2+13A-615=0$.

Can you solve for $A$?

(There are two solutions, but only one is relevant.)