Work Done by F from Po to P1 -90Nm

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A constant force F = -7i - 6j - 9k moves an object along a straight line from point (-3, 3, -3) to point (-3, 0, 5).

Find the work done if the distance is measured in meters and the magnitude of the force is measured in Newtons.

So basically I know I need to do a dot product of F with the vector between the two points, but I keep doing my math wrong.

Vector between points let's call them Po (-3,3,-3) and P1 (-3,0,5)
I found to be (0,-3,8)

So I then did the dot product between F and the Vector between Po and P1
I got -90, but my answer is wrong?
 
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Ahah a foolish negative mistake thanks for looking guys, but I found the answer
 
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