(a)

The inequality is .

Substitute in above inequality.

Multiply : .

Subtract:

\ \

Since the above statement is true, is a solution of the inequality. 

(b)

The inequality is .

Substitute in above inequality. \ \

Multiply: .

Subtract : .

Since the above statement is false, is not a solution of the inequality.

(c)

The inequality is .

Substitute in above inequality. \ \

Multiply each side by 2.

Subtract : .

Since the above statement is true, is a solution of the inequality.

(d)

The inequality is .

Substitute in above inequality. \ \

Multiply each side by 2.

Subtract : .

Since the above statement is false, is not a solution of the inequality.

(a) yes.

(b) No.

(c) yes.

(d) No.