Question 1176328


{{{6ax + 7y = -10}}}
{{{ax + 4y = -13}}}
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start with

{{{6ax + 7y = -10}}} .........solve for {{{y}}}

{{{7y = -10 -6ax }}}

{{{y = -10/7 -(6ax)/7}}}.......1)

go to

{{{ax + 4y = -13}}}......solve for {{{y}}}
 
{{{4y = -13-ax}}}
  
{{{y = -13/4-(ax)/4}}}.......2)


from  1) and 2) we have

{{{-10/7 -(6ax)/7 =-13/4-(ax)/4}}}

{{{-10/7 +13/4 =6ax/7-ax/4}}}...........multiply by {{{28}}}

{{{-40 +91 =24ax-7ax }}}

{{{51 =17ax }}}

{{{x=51/17a}}}

{{{x=3/a}}}


{{{y = -10/7 -(6ax)/7}}}..........substitute {{{x}}}

{{{y = -10/7 -(6a(3/a))/7}}}

{{{y = -10/7 -(6(3))/7}}}

{{{y = -10/7 -18/7}}}

{{{y = -28/7}}}

{{{y = -4}}}


solution set: ({{{3/a}}},{{{ -4}}}) where {{{a<>0}}}