Question

(?,5) is on the line 4x-7y=1. Find the other half of the coordinate.

Answer 1

The coordinate is an ordered pair $(x,y)$. We have a number, 5, for y, which we can substitute (plug-in) for y in the equation of the line and solve for x.

$4x-7y=1\\4x-7(5)=1\\4x=36\\x=9$

$(9,5)$