Projectile Motion Launched From Above Ground

[BakerDad12]

Hi guys, on the topic of the position of a projectile, Physics In Focus says: S_x = x₀ + u_xt and S_y = y = u_yt +1/2a_yt².

What do the x₀ and y ₀ mean? I am struggling to understand this.

Thank you so much for your time guys!!

[DrDusk]

Hi guys, on the topic of the position of a projectile, Physics In Focus says: S_x = x₀ + u_xt and S_y = y = u_yt +1/2a_yt².

What do the x₀ and y ₀ mean? I am struggling to understand this.

Thank you so much for your time guys!!

Well firstly I don't see any y₀, and the x₀ is what horizontal distance the projectile starts from with reference to your origin. For example in the x-y plane if you take (0,0) as the place of where displacement is measured and your projectile is launched from (1,0). Then it's total displacement from the reference point is 1 + u_xt where '1' is  x₀. Of course this would be different if say you were measuring from (2,0), then it would be (2)+u_xt where (2) is  x₀.