A projectile of mass 0.268 kg is shot from
a cannon, at height 6.7 m, as shown in the
ﬁgure, with an initial velocity vi having a
horizontal component of 6.9 m/s.
The projectile rises to a maximum height of
∆y above the end of the cannon’s barrel and
strikes the ground a horizontal distance ∆x
past the end of the cannon’s barrel.

Im looking for the magnitude of the final velocity and keep getting the wrong answers. Ive tried different kinematic equations to find the components of the final velocity but keep going wrong somewhere.

Question

A projectile of mass 0.268 kg is shot from
a cannon, at height 6.7 m, as shown in the
ﬁgure, with an initial velocity vi having a
horizontal component of 6.9 m/s.
The projectile rises to a maximum height of
∆y above the end of the cannon’s barrel and
strikes the ground a horizontal distance ∆x
past the end of the cannon’s barrel.

Im looking for the magnitude of the final velocity and keep getting the wrong answers. Ive tried different kinematic equations to find the components of the final velocity  but keep going wrong somewhere.