Question

A number consists of two digits whose sum is 9. If 27 is subtracted from the number its digits are reveserved.Find the number
dont use any variable except x .​

Answer 1

$let \: the \: one \: digit \: no \: is \: to \: be \: x \: \\ given \: that \: x + y = 9 \: eqation \: 1 \\ so \: the \: number \: is \: 10x + y \\ if \: 27 \: is \: subtracted \: from \: a \: number \: is \: to \: be \: reversed \: \\ so \: we \: have \: 10x + y - 27 = x + 10y \\ 9x - 9y = 27 \\ x - y = 3 \: eqation \: 2 \\ add \: 1and \: 2 \: eqation \: \\ 2x = 12 \\ x = 6 \\ subsituting \: the \: value \: we \: get \: y = 3 \\ hence \: he \: number \: is \: 63$

hope it is helpful for you ok

Answer 2

We have two ( 2 ) values so, we must use two ( 2 ) variables => ( x and y ).

Step-by-step explanation:

Let the number = xy

=10x+y

=> Sum of digits =9

=> x + y=9

=> Number −27=number with reversed digits

=> 10x+y−27=10b+x

=> 9(x−y)=27

=> x-y=3

=> (x+y)+(x−y) = 9+3

=> x=6,y=3