Find the values of the following expressions when x=-1:

(i) 2x - 7

(ii) -x + 2

(iii) x^{2} + 2x +1

(iv) 2x^{2}- x -2

(i) 2x - 7

Put x = -1

= 2(-1) - 7

= -2 - 7

= -9

(ii) -x + 2

Put x = -1

= -(-1) + 2

= 1 + 2

= 3

(iii) x^{2} + 2x + 1

Put x = -1

=(-1)^{2} + 2(-1) + 1

=1 - 2 + 1

=0

(iv)2x^{2} - x - 2

Put x = -1

=2(-1)^{2} - 1 -2

= 2(1) - 3

=2 - 3

= -1

8