At the start of the shift your part counter reads 250 at the end of the shift the part counter reads 1075 how many parts did you produce

This can be mathematically expressed to
 250 + X  = 1075
where X represents the parts you produce before the shift ends
Transpose 250 to the other side by subtracting each side by 250
Thus, it goes like this
X = 1075 - 250
X = 825

You produced 825 parts in the middle of the shift.

First subtract 10 from both side
y^2+6y-16=0
(y+8)(y-2)=0
-8 and 2