document.write( "Question 708695: What are 5 points that satisfy the equation 5y+3x=-13 ? \n" ); document.write( "
Algebra.Com's Answer #436221 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
In theory, you could give either variable a value and solve for the other variable to get one point.
\n" ); document.write( "You would do it again for each additional point.
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\n" ); document.write( "Or you could solve for one variable as a function of the other,
\n" ); document.write( "and get a formula:
\n" ); document.write( "\"5y%2B3x=-13\" --> \"5y=-3x-13\" --> \"y=-%283x%2B13%29%2F5\"
\n" ); document.write( "For any value of x, that formula makes it easy to calculate the corresponding value for y.
\n" ); document.write( "Examples:
\n" ); document.write( "\"x=0\" --> \"y=-%283%2A0%2B13%29%2F5\" --> \"y=-13%2F5\" gives you point (0,-13/5)
\n" ); document.write( "\"x=1\" --> \"y=-%283%2A1%2B13%29%2F5\" --> \"y=-%283%2B13%29%2F5\" --> \"y=-16%2F5\" gives you point (0,-16/5)
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\n" ); document.write( "However, for this equation, with those coefficients in front of x and y,
\n" ); document.write( "you will end up with a lot of fractions, and may not like the results,
\n" ); document.write( "especially if you need to use those points for a graph.
\n" ); document.write( "If you want an integer value for \"y\" you need \"3x%2B13\" to be a multiple of 5,
\n" ); document.write( "and since \"3x%2B13=3x%2B3%2B10=3%28x%2B1%29%2B5%2A2\" you would want \"x%2B1\" to be a multiple of 5,
\n" ); document.write( "like \"x%2B1=5\" --> \"x=4\"
\n" ); document.write( "\"x=4\" --> \"y=-%283%2A4%2B13%29%2F5\" --> \"y=-%2812%2B13%29%2F5\" --> \"y=-25%2F5\" --> \"y=-5\" gives you point (4,-5).
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\n" ); document.write( "If you do not need to \"show your work\" you could get additional points easily using a graph,
\n" ); document.write( "without further calculations.
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\n" ); document.write( "If you need or want to keep calculating,
\n" ); document.write( "increasing or decreasing \"x\" by 5 you will keep getting \"x%2B1\" to be a multiple of 5,
\n" ); document.write( "and will keep getting integers for y.
\n" ); document.write( "\"x=9\" gives you (9,-8)
\n" ); document.write( "\"x=-1\" gives you (-1,-2)
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\n" ); document.write( "GETTING ADDITIONAL POINTS FROM A GRAPH:
\n" ); document.write( "Once you have one point of the line, you can plot it on a graph,
\n" ); document.write( "and then you can use the slope of the line to place more points on the graph.
\n" ); document.write( "(If you do not need your graph, you may be able to get the same result adding numbers in your head,
\n" ); document.write( "or counting on your fingers).
\n" ); document.write( "From \"5y%2B3x=-13\", we could solve for y to get \"y=-%283x%2B13%29%2F5\",
\n" ); document.write( "which made it easy to calculate one point.
\n" ); document.write( "We can go further to the \"highlight%28slope-intercept%29\" form of the equation
\n" ); document.write( "\"y=-%283x%2B13%29%2F5\" --> \"highlight%28y=%28-3%2F5%29x-13%2F5%29\"
\n" ); document.write( "where the coefficient of the x is the slope of the line.
\n" ); document.write( "Going from one point in the line to another point in the line,
\n" ); document.write( "the slope is the change in y divided by the change in x.
\n" ); document.write( "A slope of \"-3%2F5\" means that
\n" ); document.write( "an increase of 5 units in x corresponds to
\n" ); document.write( "an increase of -3 units (meaning a decrease of 3 units) in y.
\n" ); document.write( "We use that fact to go from one point to the next on the graph.
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\n" ); document.write( "We move 5 units to the right (an increase of 5 for x)
\n" ); document.write( "and 3 units down (decrease of 3 for y) to mark the next point.
\n" ); document.write( "We can also reverse direction, decreasing x by 5, while increasing y by 3.
\n" ); document.write( "So after calculating (4,-5) as a first point, we could go to (9,-8) and (14,-11).
\n" ); document.write( "Reversing direction we could go to (-1,-2) and to (-6,1).
\n" ); document.write( "Without graphing:
\n" ); document.write( "I would just make a table for the x and y values and put the first point I calculate on the table.
\n" ); document.write( "In this case, I would put x=4, y=-5 in the middle.
\n" ); document.write( "Then I would fill the x values counting by 5's up and down,
\n" ); document.write( "and the y values counting by -3 (counting by 3 in the other direction):
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