document.write( "Question 268214: how do i find the solution using substitution to:
\n" ); document.write( "15x-10y=-1
\n" ); document.write( "15y=-2+5x \n" ); document.write( "

Algebra.Com's Answer #196676 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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15x - 10y =-1
\n" ); document.write( "15y = -2 + 5x
\n" ); document.write( ":
\n" ); document.write( "Use the 2nd equation for substitution
\n" ); document.write( "Rearrange to
\n" ); document.write( "5x = 15y + 2
\n" ); document.write( "divide by 5
\n" ); document.write( "x = (3y + .4)
\n" ); document.write( ":
\n" ); document.write( "Substitute (3y+.4) for x in the 1st equation
\n" ); document.write( "15(3y + .4) - 10y = -1
\n" ); document.write( "45y + 6 - 10y = -1
\n" ); document.write( "45y - 10y = -1 -6
\n" ); document.write( "35y = -7
\n" ); document.write( "y = $\"%28-7%29%2F35\"$
\n" ); document.write( "y = -.2
\n" ); document.write( ";
\n" ); document.write( "Find x:
\n" ); document.write( "x = 3y + .4
\n" ); document.write( "x = 3(-.2) + .4
\n" ); document.write( "x = -.6 + .4
\n" ); document.write( "x = -.2
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solution in the 1st equation
\n" ); document.write( "15(-.2) - 10(-.2) =-1
\n" ); document.write( "-3 + 2 = -1 \n" ); document.write( "

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