Question

sum of digits of two digit number is 9.When the digits are interchanged the new number is greater than the original number by 9.Find the original number. by linear equation in one variable ​

Answer 1

Answer:

Let unit digit is y and ten's digit is x.

Then, number will be 10x+y.

We are given,

x+y=9→(1)

When we interchange digits, number will be 10y+x

∴10x+y+27=10y+x

⇒9x−9y=−27⇒x−y=−3→(2)

Adding (1) and (2),

x+y+x−y=9−3⇒2x=6⇒x=3

∴3+y=9⇒y=6

So, two digit number will be = 3∗10+6=36