The sum of digits in a two digit number formed by two digits from 1 to 9 is 8. If 9 is added to a number then both the digits become equal. find the number.

Here we need to set a system of two linear equations in two variables. So:

Let be those digits, then:

But from eq 1:

Substituting y into the expression 1:

The x-value will be found by hit and trial, so:

We have to reject this solution because digits are different.

We have to reject this solution because digits are different.

Then this is a two digit number formed by two equal digits.

Finally, the number is:

44

answer:   rlly

step-by-step explanation: