document.write( "Question 692374: Graph the following system of linear inequalities {5x-4y≥0
\n" ); document.write( "{5x+7y≥55
\n" ); document.write( "{5x-3y≤70
\n" ); document.write( " x,y≥0\r
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\n" ); document.write( "\n" ); document.write( "Thanks for any help, I do not understand this at all.
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Algebra.Com's Answer #427329 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
You have 5 inequalities.
\n" ); document.write( "Each has a boundary (such as \"5x-4y=0\") that is included, and can be graphed as a line.
\n" ); document.write( "The other (x,y) pairs that satisfy the inequality are represented by all the points to one side of that graphed line.
\n" ); document.write( "You can use a convenient test point that is not on the line to see which side is in the solution.
\n" ); document.write( "You could graph all those inequalities separately, and find what parts of the x-y plane are common to all those graphs.
\n" ); document.write( "However, the points that satisfy all the inequalities may be part of a polygon limited by all those boundary lines.
\n" ); document.write( "The points where the boundary lines intersect could be the vertices of such a polygon and finding those points may be a better strategy.
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\n" ); document.write( "THE EASY CONSTRAINTS:
\n" ); document.write( "\"x%3E=0\" is graphed as the y-axis (the line with \"x=0\") and all the points to the right of the y-axis (all have \"x%3E0\").
\n" ); document.write( "\"y%3E=0\" is graphed as the x-axis (the line with \"y=0\") and all the points above the x-axis (all have \"y%3E0\").
\n" ); document.write( "Those 2 constraints tell us we are limited to the first quadrant.
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\n" ); document.write( "THE INTERSECTION POINTS:
\n" ); document.write( "\"system%285x-4y=0%2C5x-3y=70%29\" --> \"system%285x=4y%2C4y-3y=70%29\" --> \"system%285x=280%2Cy=70%29\" --> \"system%28x=56%2Cy=70%29\" gives point A(56,70)
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\n" ); document.write( "\"system%285x-4y=0%2C5x%2B7y=55%29\" --> \"system%285x=4y%2C4y%2B7y=55%29\" --> \"system%285x=4y%2C11y=55%29\" --> \"system%285x=20%2Cy=5%29\" --> \"system%28x=4%2Cy=5%29\" gives point B(4,5)
\n" ); document.write( "Those 2 points can be used to graph boundary line \"5x-4y=0\" (line AB)
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\n" ); document.write( "\"system%285x%2B7y=55%2Cy=0%29\" --> \"system%285x=55%2Cy=0%29\" --> \"system%28x=11%2Cy=0%29\" gives point C(11,0)
\n" ); document.write( "Point (11,0) plus previously found point (4,5) can be used to graph boundary line \"5x%2B7y=55\" (line BC)
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\n" ); document.write( "\"system%285x-3y=70%2Cy=0%29\" --> \"system%285x=70%2Cy=0%29\" --> \"system%28x=14%2Cy=0%29\" gives point D(14,0)
\n" ); document.write( "Point (14,0) plus previously found point (56,70) can be used to graph boundary line \"5x-3y=70\" (line DA)
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\n" ); document.write( "All of the above, along with test point P(10,10), can be graphed as
\n" ); document.write( " Substituted, P's coordinates satisfy all the inequalities.
\n" ); document.write( "All the points on the same side of all boundary lines as point P are solutions.
\n" ); document.write( "The solution to the system is the quadrilateral ABCD, including its boundaries.
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