Givesn
Let P = 10x + y
Let Q = 10y + x
Solve
P - Q = 54 Substitute in for x and y
10x + y - 10y - x = 54
9x - 9y = 54 Divide the entire equation by 9
x - y = 6
Start by letting x = 9
9 - y = 6 Subtract 9 from both sides.
-y = 6 - 9
-y = - 3
y = 3
Therefore P is 93 <<<< Answer
Check
93 - 39 = 54 which checks.
