Answer:
53
Step-by-step explanation:
Let x = the first digit
and y = the second digit. Then,
xy = the number
We have two conditions:
(1) x + y = 8
(2) 10y + x = 10x + y - 18
Simplify (2) 10y + x - 10x - y = -18
(3) 9y - 9x = -18
Multiply Equation (1) by 9 (4) 9x + 9y = 72
Add Equations (3) and (4) 18y = 54
Divide each side by 18 (5) y = 3
Substitute (5) into (1) x + 3 = 8
Subtract 3 from each side x = 5
x = 5 and y = 3
The number is 53.
Check:
(1) 5 + 3 = 8 (2) 10×3 + 5 = 10×5 + 3 - 18
8 = 8 30 + 5 = 50 + 3 - 18
35 = 53 - 18
35 = 35
