Question 1075912

{{{4x-5y=-11}}}....eq.1
{{{x+2y=7}}}.......eq.2
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{{{x+2y=7}}}.......eq.2......solve for {{{x}}}

{{{x=7-2y}}}.........substitute in eq.1

{{{4x-5y=-11}}}....eq.1
{{{4(7-2y)-5y=-11}}}.....solve for {{{y}}}
{{{28-8y-5y=-11}}}
{{{28-13y=-11}}}
{{{28+11=13y}}}
{{{39=13y}}}
{{{39/13=y}}}
{{{3=y}}}

go to {{{x=7-2y}}}, substitute  {{{3}}} for {{{y}}} and solve for {{{x}}}

{{{x=7-2*3}}}
{{{x=7-6}}}
{{{x=1}}}

solutions: {{{x=1}}} and {{{y=3}}}