How to tween a gui's position to another gui's position?

Hey I was just wondering how I would be able to tween a Gui to another Gui's position because whenever I try to do that it doesn't work because if I put in the position it will show up as {num,num} {num,num} but the correct formatting is (num,num,num,num).

This is the code:

function knifeSlide(knife)
    knife:TweenPosition(UDim2.new(0.5, -100,0.5, -100) , "Out" , "Quad" , .5 ,true)
    knife:TweenPosition(UDim2.new(1, -100,1, -100) , "Out" , "Quad" , .5 ,true)
end

knifeSlide(script.Parent.KnifeImage)

Thanks.