Question

What will be a 2digit no ,if the sum of its digit is equal to 9 and their diff is 3

Answer 1

let the 2 digit number be 10x+y

x+y=9

x-y=3 or y-x=3

on solving the 2

x=6 or x=3

y=3 or y=6

therefore 2 numbers are possible and they are 36 and 63

Answer 2

let the two digit number be x at tens place and y at ones place

so according to the condition:

x+y=9 -1

x-y=3. -2

on subtracting 1 and 2 we get

2y=6

y=3

put y=3 in equation 1

x+3=9

x=6

so we have x=6 and y=3

therefore two digit number is 63