Question 927118


the sum of two numbers, {{{x}}} and {{{y}}}, is {{{11}}} and their difference is {{{6}}}

{{{x+y=11}}}...eq.1

{{{x-y=6}}}....eq.2
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start with
{{{x+y=11}}}...eq.1..solve for {{{y}}}

{{{y=11-x}}}...substitute in eq.2


{{{x-(11-x)=6}}}....eq.2.solve for {{{x}}}


{{{x-11+x=6}}}


{{{2x=6+11}}}

{{{2x=17}}}

{{{x=17/2}}}

{{{highlight(x=8.5)}}}

now find {{{y}}}


{{{y=11-x}}}

{{{y=11-8.5}}}

{{{highlight(y=2.5)}}}


check:

{{{x+y=11}}}...eq.1=>{{{8.5+2.5=11}}}=>{{{11=11}}}

{{{x-y=6}}}....eq.2=>{{{8.5-2.5=6}}}=>{{{6=6}}}