Would y=5/2x+4 and y=2/5x-8/5 be parallel, perpendicular or neither to each other

The slopes of the lines y = (5/2)x+4 and y = (2/5)x-8/5 are 5/2 and 2/5 respectively in that order.

The two fractions 5/2 and 2/5 are not equal
5/2 = 2.5
2/5 = 0.4
So the lines are not parallel.

Multiply the two slopes and we get
(5/2)*(2/5) = (5*2)/(2*5) = 10/10 = 1
The result isn't -1 so the two lines aren't perpendicular either.

Final Neither

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