Question

What would be the △Y and the △X for the line that passes through the points (–5, 4) and (2, –2)

Answer 1

That triangle means "delta" which means "change in".  The change in y is the difference between the y coordinates; the change in x is the difference between the x coordinates.  The change in y is -2-4 which is -6, and the change in x is 2-(-5) which is 7.