```Question 24428
The first equation is ambiguous!
Is it {{{y = (2/3)x}}} or {{{y = 2/3x}}}???
Let's assume that it is the first case.

You can solve questions like this by graphing or algebraically.
Let's look at the graphic solution:
{{{graph(300,200,-5,5,-5,5,(2/3)x,2x+4)}}}
The red line is {{{y = (2/3)x}}}
The green line is {{{y = 2x+4}}} This is the 2nd equation written in terms of y.

Now solve algebraically by substitution:
1) {{{y = (2/3)x}}} Substitute this equation for y in the second equation.
2) {{{2x-y = -4}}}

2) {{{2x-(2/3)x = -4}}} Simplify and solve for x.
{{{(4/3)x = -4}}} Multiply both sides by the multiplicative inverse of 4/3 (that's 3/4)
{{{x = -3}}} Now substitute this value of x into either one of the two original equations and solve for y. Take the first equation, {{{y = (2/3)x}}}
{{{y = (2/3)(-3)}}}
{{{y = -2}}}

There is only one solution, it is: (-3, -2) Compare this with the intersection point of the two lines on the graph.

Now assume that the first equation is: {{{y = 2/3x}}} and let's look at the graph:
{{{graph(300,200,-5,5,-5,5,2/(3x),2x+4)}}}
As you can see, there would be two solutions (points of intersection) in this case.```