Which of the following expressions represents a function?

a.{(1,,-,,-3)}
b. y^2=16-x^2
c.2x^2+y^2=5
d. x=7

constant acceleration- a

constant velocity- c

no velocity or acceleration- b

explanation:

for body moving with a constant acceleration, the rate of change of displacement changes over time. this is proven by the increasing gradient of the curve (a) against time.

a body that is moving at constant velocity covers equal distances over equal periods of time, thus the straight line with a constant gradient c.

a stationary body   covers no displacement as time elapses. thus the flat line with   zero gradient.

ab: 2 n83b8eb7ebi. 8e yen in