If x = 5 nad y = -2 , then x -2y =9, the contrapositive of this proposition is

Options

A. If x -2y is not equal to 9 , then ` x ne 5 or y ne -2`
B. ` if x -2y =9, x ne 5 and y ne -2`
C. ` x -2y =9 if and " only " if x=5 and y =-2 `
D. none of these

Answer

A

Explanation

Let p q and r be three propositions given by
p : x=5, y = -2 and r -2y =9
then , the given statement is ` (p vv q) to r ` its contrapositive is
` ~ r to ~ ( p ^^ q)`
i.e ` ~ r to ~ p vv ~ q `
i.e if ` x -2y ne 9, " then " x ne 5 or y ne -2`