Question

PLEASE answer it....​

Answer 1

let x be in tenths place and y be in units place

according to question, the desired no.is 10x+y

and sum of the digits is x+y

so,10x+y=8(x+y)....1

on solving,we get

2x=7y...2

10x+y=14(x-y)+2.....3

on solving we get

24x-13y=2.......4

solving eqn 2 and 3 we get,

y=2/71

This is not possible,since y cannot be in a fraction form so the desired number is 72.

Answer 2

let the 2 digit number be x and y

case 1...(x+y)8=10x+y

8x+8y=10x+y

7y=2x

7y-2x=0.......... (1)

case 2... (x-y)14+2=10x+y

14x-14y+2=10x+y

4x-13y +2=0........ (2)

from equation (1) y =2x/7

put this value in (2)

you get .....4x-13×2x/7+2=0

4x-26x/7 +2 =0

2x/7=-2

x=-7 since x cant be in negative we take +7
so number is 72
put this in (1) you get y=2