Respuesta :

apologiabiology
x and y  are digts
x is tens y is ones

x=y+5

10y+x=10x+y-45
x+y=9


we have
x+y=9
x=y+5
sub
y+5+y=9
2y+5=9
minus 5
2y=4
divide 2
y=2

sub back
x=y+5
x=2+5
x=7

the number is 72