y = x

(i) y = -x

(ii) y = 2x

y = 2x the graph moves away the x-axis, as multiplying factor is 2 which is greater than one.
(iii) y = 2x + 1

(iv) y = (1/2)x + 1

y = (1/2)x moves towards x – axis by a side factor (1/2) which is less than y = (1/2)x + 1 upwards by 1 unit.
(v) y = -2x – 3
