Question 1132158

 {{{4x+7y=-9 }}}.........eq.1
{{{3x=3y+18  }}}.........eq.2........solve for {{{x}}}
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{{{x=3y/3+18/3  }}}.........eq.2
{{{x=y+6  }}}.............substitute in eq.1
 
{{{4(y+6 )+7y=-9 }}}

{{{4y+24+7y=-9 }}}

{{{11y=-9-24 }}}

{{{11y=-33  }}}

{{{y=-3 }}}

go to {{{x =y+6 }}}........., substitute {{{y}}}

{{{x =-3+6 }}}

{{{x =3}}}

solution:

({{{3}}},{{{-3}}})

{{{ graph( 600, 600, -10, 10, -10, 10, x-6, -4x/7-9/7) }}}