document.write( "Question 173846: Can you help me find a solution? I used a substitution method by it seem it does not work.
\n" ); document.write( "1.The Everton college store paid $1660 for an order of 44 calculators. The store paid $11 for each scientific calculator. The others, all graph calculators, cost the store $53 each. How many of each type of calculator was order?\r
\n" ); document.write( "\n" ); document.write( "The store ordered__scientific calculators and __graphing calculators.\r
\n" ); document.write( "\n" ); document.write( "2. Elimination method
\n" ); document.write( " 0.3x-0.2y=4
\n" ); document.write( " 0.2x+0.3y=-23/19\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "3. Substitution method\r
\n" ); document.write( "\n" ); document.write( " 6x+7y=-22
\n" ); document.write( " -3x+y=20
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #128723 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
1.The Everton college store paid $1660 for an order of 44 calculators. The store paid $11 for each scientific calculator. The others, all graph calculators, cost the store $53 each. How many of each type of calculator was order?
\n" ); document.write( "---
\n" ); document.write( "Value equation: 11s + 53g = 1660
\n" ); document.write( "Quantity equation: s + g = 44
\n" ); document.write( "--------
\n" ); document.write( "Substitution Method:
\n" ); document.write( "s = 44-g
\n" ); document.write( "Substitute into the 1st equation:
\n" ); document.write( "11(44-g) + 53g = 1660
\n" ); document.write( "484 - 11g + 53g = 1660
\n" ); document.write( "42g = 1176
\n" ); document.write( "g = 28 (# of graphing calculators purchased)
\n" ); document.write( "---------
\n" ); document.write( "Substitute into s = 44-g to get:
\n" ); document.write( "s = 44-28 = 16 (# of scientific calculators purchased)
\n" ); document.write( "--------------------------------------------------------------\r
\n" ); document.write( "\n" ); document.write( "2. Elimination method
\n" ); document.write( "0.3x-0.2y=4
\n" ); document.write( "0.2x+0.3y=-23/19
\n" ); document.write( "-------
\n" ); document.write( "Modify the equations:
\n" ); document.write( "3x - 2y = 40
\n" ); document.write( "2x + 3y = -230/19
\n" ); document.write( "---------------------
\n" ); document.write( "Modify for elimination:
\n" ); document.write( "6x - 4y = 80
\n" ); document.write( "6x + 9y = -690/19
\n" ); document.write( "-------------------
\n" ); document.write( "Substract 1st from 2nd to get:
\n" ); document.write( "13y =(-690/19) - 80 = -116.3158
\n" ); document.write( "y = -8.9474
\n" ); document.write( "------------
\n" ); document.write( "Substitute into 3x-2y=40 to solve for x:
\n" ); document.write( "3x - 2(-8.9474) = 40
\n" ); document.write( "3x = 22.1053
\n" ); document.write( "x = 7.3684333...
\n" ); document.write( "---------------------
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \r
\n" ); document.write( "\n" ); document.write( "3. Substitution method
\n" ); document.write( "6x+7y=-22
\n" ); document.write( "-3x+y=20
\n" ); document.write( "
\n" ); document.write( "
\n" );