Question 253274
{{{x+2y=4}}} Start with the first equation.



{{{x+2(-(1/2)x+2)=4}}} Plug in {{{y=-(1/2)x+2}}}



{{{x-x+4=4}}} Distribute



{{{0x+4=4}}} Combine like terms on the left side.



{{{0x=4-4}}} Subtract {{{4}}} from both sides.



{{{0x=0}}} Combine like terms on the right side.



{{{0=0}}} Simplify.



Since this equation is <font size=4><b>ALWAYS</b></font> true for any x value, this means x can equal any number. 



So there are an infinite number of solutions.