Question 151206
{{{3*x-4*y+9}}} Start with the given expression.



{{{3*2-4*5+9}}} Plug in {{{x=2}}} and {{{y=5}}} 



{{{6-4*5+9}}} Multiply {{{3}}} and {{{2}}} to get {{{6}}}.  



{{{6-20+9}}} Multiply {{{4}}} and {{{5}}} to get {{{20}}}.  



{{{-14+9}}} Subtract {{{20}}} from {{{6}}} to get {{{-14}}}.  



{{{-5}}} Add {{{-14}}} and {{{9}}} to get {{{-5}}}.  



So {{{3*x-4*y+9=-5}}} when {{{x=2}}} and {{{y=5}}}