document.write( "Question 1134703: Solve the equations using elimination and substitution
\n" ); document.write( "（1）2x+3y=11
\n" ); document.write( "4x+y=12
\n" ); document.write( "（2）3x+2y=24
\n" ); document.write( "2x-3y=42 \n" ); document.write( "

Algebra.Com's Answer #752163 by Boreal(15235) $\"\"$ $\"About$

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First by substitution
\n" ); document.write( "y=-4x+12
\n" ); document.write( "substitute into the top to get 2x+3(-4x+12)=11
\n" ); document.write( "2x-12x+36=11
\n" ); document.write( "-10x=-25
\n" ); document.write( "x=2.5
\n" ); document.write( "substitute into second and y=2
\n" ); document.write( "check in top one and 2(2.5)+3(2) does =11
\n" ); document.write( "(2.5, 2)
\n" ); document.write( "Do by elimination
\n" ); document.write( "multiply top by -2
\n" ); document.write( "-4x-6y=-22
\n" ); document.write( "4x+y=12
\n" ); document.write( "-5y=-10
\n" ); document.write( "y=2
\n" ); document.write( "x=2.5\r
\n" ); document.write( "\n" ); document.write( "Do the second by elimination
\n" ); document.write( "Multiply the top by 3 and the bottom by 2, which will make 6y and -6y which cancel each other
\n" ); document.write( "9x+6y=72
\n" ); document.write( "4x-6y=84
\n" ); document.write( "13x=156
\n" ); document.write( "x=12
\n" ); document.write( "y=-6
\n" ); document.write( "(12, -6), and that checks
\n" ); document.write( "One can do substitution but more difficult here. x=(-2/3)y+8 or y=(-3/2)x+12 and put into the second equation. \n" ); document.write( "

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