Question 27626
ok, first for the easier part:
2x-3=7
2x = 10
x = 5


this solution is seen on the graph of y=2x-3 and y=7... they intersect at x=5, as shown: {{{graph(200,200,-10,10,-25,25,2x-3, 7)}}}


Now the action of the modulus around the 2x-3 means that it will not allow negative values of y, so to the left of x=1.5, the straight line will "break" into a V shape and head back up to the top left


Now, mathematically, to see this "rebounded" portion of the line, we put a negative sign in front of the equation, like -(2x-3) = 7.


-2x+3 = 7
-2x = 4
x = -2


This can be seen if we ploy y = -(2x-3) against y=7, as shown: {{{graph(200,200,-10,10,-25,25,-2x+3, 7)}}}


jon.