seeking help finding the initial velocity of a type 3 projectile

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pluralangel
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Homework Statement
a projectile is launched 40° above the horizontal and lands a vertical distance of 0.943 m below and a horizontal distance of 2.4 m away; what is the initial velocity of the projectile?
Relevant Equations
vy = v sin θ
vx = v cos θ
v = Δd / Δt (constant velocity)
Δd = v1 Δt + 0.5a Δt^2 (uniform acceleration)
hi, so I've been trying to find the initial velocity of this projectile; but i ended up getting a negative value for seconds squared. I've gone over my solution multiple times but don't see where i went wrong. alternatively, was i supposed to take the absolute value of seconds squared?

thanks in advance for any help : )

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PeroK said:
Which sign are you using for the upwards direction?
up would be negative
 
PeroK said:
And your initial velocity in the ##y## direction is?
ooh, it would have to be negative v1 sin θ ?
 
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thanks so much ^_^