<PRE><B>Question 291128</B>
{{{2x+9y=16}}} Start with the given equation.



{{{2(4)+9(-4)=16}}} Plug in {{{x=4}}} and {{{y=-4}}}



{{{8-36=16}}} Multiply



{{{-28=16}}} Subtract



Since the equation above is NOT true, this means that the values {{{x=4}}} and {{{y=-4}}} do NOT satisfy the original equation. So (4,-4) is NOT a solution of {{{2x+9y=16}}}.</PRE>