document.write( "Question 936600: Please help me with these problems, I'm really confused. :( Thank you!\r
\n" ); document.write( "\n" ); document.write( "How many solutions do the following systems of equations have? Justify your answer.\r
\n" ); document.write( "\n" ); document.write( "a. -2x + 4y = 1, 3x - 6y = 9 \r
\n" ); document.write( "\n" ); document.write( "b. x + y = 8, 2x + 2y = -1 \r
\n" ); document.write( "\n" ); document.write( "c. y = (1/2)x - 4, x - 2y = 8
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Algebra.Com's Answer #570051 by josgarithmetic(39620)\"\" \"About 
You can put this solution on YOUR website!
Are slopes of a pair of equations equal or unequal?
\n" ); document.write( "Slopes equal, means the pair of lines either parallel or identical; if parallel but equations are not identical, then no point of intersection. If equations of the lines are identical, then this just means that the pair is not really a pair, so just are the same line.\r
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\n" ); document.write( "\n" ); document.write( "If the slopes are unequal, then the pair intersect in exactly one point.\r
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\n" ); document.write( "\n" ); document.write( "Convert each pair of equations into the same form and simplify. Suggested form could be slope-intercept. You could choose standard form if you prefer, as long as you know what the parts of the equational form mean.\r
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\n" ); document.write( "\n" ); document.write( "(b):
\n" ); document.write( "\"x%2By=8\" and \"2x%2B2y=-1\"
\n" ); document.write( "Simplified into
\n" ); document.write( "\"x%2By=8\" and \"x%2By=-1%2F2\";
\n" ); document.write( "Same slope, but different constant value for their right-hand members. These lines are parallel and have no solution as a system. They do not intersect.
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