Question 30652
10X+Y=6(X+Y) & X=Y+1 SUBSTITUTION Y+1 FOR X IN THE FIRST EQUATION WE GET

10(Y+1)+Y=6((Y+1)+Y) OR 10Y+10+Y=6Y+6+6Y OR 11Y+10=12Y+6 OR -Y=-4 OR Y=4

THEREFORE X=4+1 OR X=5 THUS THE NUMBER IS 54 BECAUSE 5+4=9 AND 54=6 TIMES 9