document.write( "Question 184605: For what values of c will the system have:\r
\n" ); document.write( "\n" ); document.write( "infinitely many solution
\n" ); document.write( "1) 2x - 6y = c
\n" ); document.write( " 6x - 18y = 30\r
\n" ); document.write( "\n" ); document.write( "2)no solution
\n" ); document.write( " x + 2y = 6
\n" ); document.write( " cx - 4y = 8\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "How do you do these questions? Can you explain how?
\n" ); document.write( "

Algebra.Com's Answer #138550 by vleith(2983)\"\" \"About 
You can put this solution on YOUR website!
infinitely many solution
\n" ); document.write( "1) 2x - 6y = c
\n" ); document.write( " 6x - 18y = 30
\n" ); document.write( "infinitely many solution means the two 'lines' are really the same line
\n" ); document.write( "the second line above has two terms that are exactly 3 times the terms of the fisrt line (6x = 3*2x and -18y = 3 *(-6y)) so if c is 3*30, then the two lines are really the same line.\r
\n" ); document.write( "\n" ); document.write( "2)no solution
\n" ); document.write( " x + 2y = 6
\n" ); document.write( " cx - 4y = 8\r
\n" ); document.write( "\n" ); document.write( "No solution occurs when the 'answer' is something that can't happen
\n" ); document.write( "So let's double the first line to get
\n" ); document.write( "2x + 4y = 12
\n" ); document.write( "Now add the second line to it
\n" ); document.write( "2x + 4y = 12
\n" ); document.write( "cx -4y = 8
\n" ); document.write( "----------
\n" ); document.write( "(2+c)x = 20
\n" ); document.write( "any c that that makes (2+x) a non-zero number will result in an x that 'works'. However, if c = -2, then we get
\n" ); document.write( "(0*x) = 20
\n" ); document.write( "0 times anything is 0, so that yields
\n" ); document.write( "0 = 20\r
\n" ); document.write( "\n" ); document.write( "0=20 is impossible, so is c = -2 then ther eis no solution.,\r
\n" ); document.write( "\n" ); document.write( "make sense?
\n" ); document.write( "
\n" );