document.write( "Question 827923: Determine which of the following points are solutions to the system of equations.
\n" ); document.write( "{3x + 2y =5
\n" ); document.write( "{x + 2y = 7
\n" ); document.write( "A. (3, 0)
\n" ); document.write( "B. (−1, 4)
\n" ); document.write( "C. (3, 0)
\n" ); document.write( "D. (4, −1)\r
\n" ); document.write( "\n" ); document.write( "Please show work
\n" ); document.write( "

Algebra.Com's Answer #498937 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: Solve the System of Equations by Graphing

\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " Start with the given system of equations:
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"3x%2B2y=5\"
\n" ); document.write( "
\n" ); document.write( " \"1x%2B2y=7\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " In order to graph these equations, we need to solve for y for each equation.
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So let's solve for y on the first equation
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"3x%2B2y=5\" Start with the given equation
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"2y=5-3x\" Subtract \"3+x\" from both sides
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"2y=-3x%2B5\" Rearrange the equation
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-3x%2B5%29%2F%282%29\" Divide both sides by \"2\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-3%2F2%29x%2B%285%29%2F%282%29\" Break up the fraction
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-3%2F2%29x%2B5%2F2\" Reduce
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " Now lets graph \"y=%28-3%2F2%29x%2B5%2F2\" (note: if you need help with graphing, check out this solver)
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%28-3%2F2%29x%2B5%2F2%29+\" Graph of \"y=%28-3%2F2%29x%2B5%2F2\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So let's solve for y on the second equation
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"1x%2B2y=7\" Start with the given equation
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"2y=7-x\" Subtract \"+x\" from both sides
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"2y=-x%2B7\" Rearrange the equation
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-x%2B7%29%2F%282%29\" Divide both sides by \"2\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-1%2F2%29x%2B%287%29%2F%282%29\" Break up the fraction
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-1%2F2%29x%2B7%2F2\" Reduce
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " Now lets add the graph of \"y=%28-1%2F2%29x%2B7%2F2\" to our first plot to get:
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " Graph of \"y=%28-3%2F2%29x%2B5%2F2\"(red) and \"y=%28-1%2F2%29x%2B7%2F2\"(green)
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"-1\",\"4\") (note: you might have to adjust the window to see the intersection)

\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "answer: B. (−1, 4)
\n" ); document.write( "
\n" );