A projectile is given an initial velocity of ` ( hat(i) + 2 hat (j) ) m//s`, where ` hat(i)` is along the ground and `hat (j)` is along the vertical . If ` g = 10 m//s^(2) `, the equation of its trajectory is :
A. `y = 2x - 5x^2`
B. `y =x - 5 x^2`
C. `4 y = 2x - 5x^2`
D. `y = 2x - 25 x^2`