Question 1157002
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 Solve the system by substitution.
  A) 3x+4y=11.     B) 3x+2y=6
     -8x-y=19.         2x+5y=-7
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B was already explained and the best way could be to multiply first equation by 2, second equation by 3, and substitute for 6x.  


A:
{{{system(3x+4y=11,-8x-y=19)}}}
First easiest to SOLVE FOR y in second equation.
{{{-y=19+8x}}}
{{{y=-8x-19}}}
SUBSTITUTE into other equation.
{{{3x+4(-8x-19)=11}}}
{{{3x-32x-76=11}}}
{{{-29x=76+11}}}
{{{-29x=87}}}
{{{x=-3}}}--------------now use this to solve for y, either equation.