100 баллов даю помогиииите

10x + y - двузначное число
x + y = 9 => y = 9 - x
(y - x)×5.4 = 10x + y
(9 - 2x) × 5.4 = 9x + 9
48.6 - 10.8x = 9x + 9
0 = 19.8x - 39.6
19.8x = 39.6
x = 2
y = 7 => 10x + y = 27