document.write( "Question 346098: I need to find the intersecting points of two equations: y=.15x and y=.2(x-20)and graph them. I have included my problem and what is expected. I'm lost.\r
\n" ); document.write( "\n" ); document.write( "Ok this is what I got :
\n" ); document.write( "You would set the two equations equal to each other and solve for x
\n" ); document.write( " .15x=.2(x-20) using the Elimination Method\r
\n" ); document.write( "\n" ); document.write( "Reorder the terms:
\n" ); document.write( "0.15x = 0.2(-20 + x)
\n" ); document.write( "0.15x = (-20 * 0.2 + x * 0.2)
\n" ); document.write( "0.15x = (-4 + 0.2x)\r
\n" ); document.write( "\n" ); document.write( "Solving
\n" ); document.write( "0.15x = -4 + 0.2x\r
\n" ); document.write( "\n" ); document.write( "Solving for variable 'x'.\r
\n" ); document.write( "\n" ); document.write( "Move all terms containing x to the left, all other terms to the right.\r
\n" ); document.write( "\n" ); document.write( "Add '-0.2x' to each side of the equation.
\n" ); document.write( "0.15x + -0.2x = -4 + 0.2x + -0.2x\r
\n" ); document.write( "\n" ); document.write( "Combine like terms: 0.15x + -0.2x = -0.05x
\n" ); document.write( "-0.05x = -4 + 0.2x + -0.2x\r
\n" ); document.write( "\n" ); document.write( "Combine like terms: 0.2x + -0.2x = 0.0
\n" ); document.write( "-0.05x = -4 + 0.0
\n" ); document.write( "-0.05x = -4\r
\n" ); document.write( "\n" ); document.write( "Divide each side by '-0.05'.
\n" ); document.write( "x = 80\r
\n" ); document.write( "\n" ); document.write( "Simplifying
\n" ); document.write( "x = 80\r
\n" ); document.write( "\n" ); document.write( "Now that X = 80, I plugged it into the equation y=0.15x and got this:
\n" ); document.write( "y=0.15x
\n" ); document.write( "y=0.15(80)
\n" ); document.write( "y= 12\r
\n" ); document.write( "\n" ); document.write( "Now this is the question to my problem and I do not know how to get the answer. I have to graph this and show the intersection.\r
\n" ); document.write( "\n" ); document.write( "a teacher is looking for the best option in purchasing school supplies for a classroom. Where Company A is offering a discount for every dollar amount spent on school supplies and where Company B is offering a higher discount than Company A, but the discount for Company B is only offered for every dollar amount spent above $20.00. I will determine and explain which company will offer a better price based upon the dollar amount the teacher spends on school supplies.\r
\n" ); document.write( "\n" ); document.write( "Option 1- Company A will offer her a 15% discount on the total amount spent in the store.
\n" ); document.write( "Option 2- Company B will offer her a 20% discount on the remaining amount after the first $20 is spent.\r
\n" ); document.write( "\n" ); document.write( "Depict the situation graphically, using appropriate graphing software such as Excel or an online graphing utility.\r
\n" ); document.write( "\n" ); document.write( "Include the following in your graph:
\n" ); document.write( "• A depiction of each cost option on the same graph
\n" ); document.write( "• Clear labels of the cost to the hypothetical customer for both options on the graph
\n" ); document.write( "• The intersection of the cost options (if one exists)\r
\n" ); document.write( "\n" ); document.write( "I'm so lost. I do not know how to graph this. Please help if you can.
\n" ); document.write( "

Algebra.Com's Answer #247480 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
First your answer is correct.
\n" ); document.write( "Now plotting.
\n" ); document.write( "\"y=0.15x\"
\n" ); document.write( "When \"x=0\", \"y=0\"
\n" ); document.write( "when \"x=100\",\"y=15\"
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\n" ); document.write( "Plot the points and the line connecting them.
\n" ); document.write( "The x-axis is the amount of money you spend.
\n" ); document.write( "The y-axis is the discount you receive.
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\n" ); document.write( "The red line is the savings from the Company A plan.
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\n" ); document.write( "The Company B savings only begins at \"x=20\".
\n" ); document.write( "So you have to spend at least $20 to receive any discount.
\n" ); document.write( "\"y=.2%28x-20%29\"
\n" ); document.write( "When \"x=20\",\"+y=0\"
\n" ); document.write( "When \"x=100\", \"y=0.2%28100-20%29=16\"
\n" ); document.write( "Plot those points and line.
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\n" ); document.write( "The blue line is the savings from the Company B plan.
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\n" ); document.write( "When does the Company B plan savings equal the Company A plan savings.
\n" ); document.write( "You already calculated that point.
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\n" ); document.write( "When you spend $80, you get a savings from both plans of $12.
\n" ); document.write( "Plot that point too.
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\n" ); document.write( "Once you pass that point ($80), Company B savings (blue line) are higher than Company A.
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\n" ); document.write( "If you spend less than $80, Company A savings (red line) are higher than Company B.
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