document.write( "Question 65559: Solve each of the following systems by addition. If a unique solution does not exist, state whether the system is inconsistent or dependent.
\n" ); document.write( "x +5y = 10
\n" ); document.write( "-2x – 10y = -20\r
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\n" ); document.write( "\n" ); document.write( "Solve each of the following problems. Be sure to show the equations used for the solution.
\n" ); document.write( "Number problems. Jill has $3.50 in nickels and dimes. If she has 50 coins, how many of each type of coin does she have?\r
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\n" ); document.write( "\n" ); document.write( "Business and finance. A coffee merchant has coffee beans that sell for $9 per pound and $12 per pound. The two types are to be mixed to create 100 Lb of a mixture that will sell for $11.25 per pound. How much of each type of bean should be used in the mixture?
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Algebra.Com's Answer #46141 by stanbon(75887)\"\" \"About 
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Solve each of the following systems by addition. If a unique solution does not exist, state whether the system is inconsistent or dependent.
\n" ); document.write( "1st: x +5y = 10
\n" ); document.write( "2nd: -2x – 10y = -20
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\n" ); document.write( "Let's say you choose to eliminate the x-terms by adding.
\n" ); document.write( "Since the coefficient of the 2nd equation is -2x you want
\n" ); document.write( "to create +2x in the 1st equation; so you multiply both
\n" ); document.write( "sides of the 1st equation by 2 as follows:
\n" ); document.write( "2(x+5y)=2(10)
\n" ); document.write( "3rd: 2x+10y=20
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\n" ); document.write( "Then you add the 2nd and 3rd equations to get:
\n" ); document.write( "0=0
\n" ); document.write( "This means equation #2 says the same thing as equation #3.
\n" ); document.write( "The system is dependent.
\n" ); document.write( "This means the two equations are really the same.
\n" ); document.write( "It also means that every point in the line x+5y=10 is a solution
\n" ); document.write( "point for the system of equations.
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\n" ); document.write( "\n" ); document.write( "Solve each of the following problems. Be sure to show the equations used for the solution.
\n" ); document.write( "Number problems. Jill has $3.50 in nickels and dimes. If she has 50 coins, how many of each type of coin does she have?
\n" ); document.write( "Let number of nickels be \"x\"; Value of these is 10x cents
\n" ); document.write( "Number of dimes is \"50-x\"; Value of these is 10(50-x)=(500-10x)cents
\n" ); document.write( "EQUATION:
\n" ); document.write( "value + value= 350cents
\n" ); document.write( "10x+500-10x=350
\n" ); document.write( "0=-150
\n" ); document.write( "This is a contradiction.
\n" ); document.write( "The system is inconsistent
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\n" ); document.write( "\n" ); document.write( "Business and finance. A coffee merchant has coffee beans that sell for $9 per pound and $12 per pound. The two types are to be mixed to create 100 Lb of a mixture that will sell for $11.25 per pound. How much of each type of bean should be used in the mixture?
\n" ); document.write( "Amount of $9 is \"x\" lbs; Value is 9x dollars
\n" ); document.write( "Amount of $12 is \"100-x\"; Value is 12(100-x)=1200-12x dollars
\n" ); document.write( "Amount of mixture is 100 lb; Value is 11.25(100)=1125 dollars
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\n" ); document.write( "EQUATION:
\n" ); document.write( "value + value = 1125 dollars
\n" ); document.write( "9x+1200-12x=1125
\n" ); document.write( "-3x=-75
\n" ); document.write( "x=25 lb (amount of $9 coffee)
\n" ); document.write( "100-x=75 lb (amount of $12 coffee)
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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