document.write( "Question 1079288: Find numbers a and b so that the system of equations
\n" ); document.write( "{3x+y = 5
\n" ); document.write( "x−ay = b
\n" ); document.write( "has (i) no solutions, (ii) infinitely many solutions, and (iii) a unique solution at (1,2). Graph the two lines in all three situations.
\n" ); document.write( "

Algebra.Com's Answer #693611 by ikleyn(52906)\"\" \"About 
You can put this solution on YOUR website!
.
\n" ); document.write( "Find numbers a and b so that the system of equations
\n" ); document.write( "3x + y = 5
\n" ); document.write( "x - ay = b
\n" ); document.write( "has \r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\r\n" );
document.write( "(i) no solutions                         If a = \"-1%2F3\" and b =/= \"5%2F3\" then the system HAS NO solutions.\r\n" );
document.write( "                                         Indeed, the left sides of equations are proportional with the coefficient 3 (First to the Second),\r\n" );
document.write( "                                         while the right sides are not proportional with the same coefficient.\r\n" );
document.write( "\r\n" );
document.write( "                                         The plot is two distinct parallel lines with NO intersection.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "(ii) infinitely many solutions            If a = \"-1%2F3\" and b = \"5%2F3\" then the system HAS INFINITELY NANY solutions.\r\n" );
document.write( "                                         Indeed, the left sides of equations are proportional with the coefficient 3 (First to the Second),\r\n" );
document.write( "                                         while the right sides are not proportional with the same coefficient.\r\n" );
document.write( "                                         Therefore, every solution to the first equation is the solution to the second equation.\r\n" );
document.write( "                                         Thus the two equations are equivalent to one, either of the two.\r\n" );
document.write( "                                         The plot is two coinsiding parallel lines with infinitely many common points . . .\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "(iii) a unique solution at (1,2).       If a =/= \"-1%2F3\" then the system has a unique solution.\r\n" );
document.write( "                                        The plot is two non-parallel straight lines that have a unique intersection, which represents \r\n" );
document.write( "                                        the common solution to the system.\r\n" );
document.write( "
\r
\n" ); document.write( "\n" ); document.write( "See the lesson\r
\n" ); document.write( "\n" ); document.write( "    - Geometric interpretation of a linear system of two equations in two unknowns \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Systems of two linear equations in two unknowns\".\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );