document.write( "Question 106372: Hello out there,I really need some help with some problems,the first one is,State whether the system is consistent and independent,consistent and dependent,or inconsistent:4x+2y=8 and 2x+y=1.The next one is,State whether the system is consistent and independent,consistent and dependent,or inconsistent:x+y=4 and 2x-y=-7.The third one is,Determine whether the system has one solution,no solution,or infinitely many solutions:y=-x+2 and 3x+3y=6.And the last one is,Determine whether the system has one solution,no solution,or infinitely many solutions:y=2/3x and 2x-y=-4.Thanks to whoever can help. \n" ); document.write( "
Algebra.Com's Answer #77484 by elima(1433)![]() ![]() ![]() You can put this solution on YOUR website! 4x+2y=8 \n" ); document.write( "2x+y=1 \n" ); document.write( "--------- \n" ); document.write( "We will solve this by elimination since you don't say which to use; \n" ); document.write( "1)4x+2y=8 \n" ); document.write( "2)2x+y=1 \n" ); document.write( "we will multiply a -2 to the second equation to eliminate the y; \n" ); document.write( "(-2)2x+y=1 \n" ); document.write( "-4x-2y=1 \n" ); document.write( "------------- \n" ); document.write( "Now lets add the two equations together; \n" ); document.write( "4x+2y=8 \n" ); document.write( "-4x-2y=-2 \n" ); document.write( "-------- \n" ); document.write( "0=-2 \n" ); document.write( "Since this is o=-2, it is inconsistent \n" ); document.write( "============================================== \n" ); document.write( "With this next one, when you add them together they already eliminate a variable, so no other multiplying is necessary; \n" ); document.write( "x+y=4 \n" ); document.write( "2x-y=-7 \n" ); document.write( "-------- \n" ); document.write( "3x=-3 \n" ); document.write( "x=-1 \n" ); document.write( "Now substitute the -1 for x in one of the equations; \n" ); document.write( "-1+y=4 \n" ); document.write( "y=5 \n" ); document.write( "Since this has only one answer for x and y it is consistent and independent \n" ); document.write( "=============================================================================== \n" ); document.write( "y=-x+2 \n" ); document.write( "3x+3y=6 \n" ); document.write( "x+y=2 \n" ); document.write( "-3x-3y=-6 \n" ); document.write( "3x+3y=6 \n" ); document.write( "--------- \n" ); document.write( "0=0 \n" ); document.write( "This is the same line so it is infinitely many solutions \n" ); document.write( "=============================================================== \n" ); document.write( "y=2/3x \n" ); document.write( "2x-y=-4 \n" ); document.write( "-----------------\r \n" ); document.write( "\n" ); document.write( "-2/3)x+y=0 \n" ); document.write( " 2x-y=-4 \n" ); document.write( "---------- \n" ); document.write( " \n" ); document.write( "x=-3 \n" ); document.write( " \n" ); document.write( "y=-2 \n" ); document.write( "This has only one point, so it has only one solution \n" ); document.write( ":) \n" ); document.write( " \n" ); document.write( " |