Question 98285
4-2*3=7
4-6=7
-2 Does not equal 7. Therefore (4,3) is not an answer.
x-2y=7
-2y=-x+7
y=-x/-2+7/-2
y=-.5x+-3.5 This is the line formula.
{{{ graph( 300, 200, -6, 5, -10, 10, y = -.5x -3.5) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, y = -.5x -3.5). 
As you can see the point (4,3) is not on the line. Therefore they are not a solution.