document.write( "Question 65196: Will you please help me with this problem?\r
\n" ); document.write( "\n" ); document.write( "Write a system of two equations in two unknowns. Solve the system by using the addition method. « Mike paid $2.98 for three doughnuts and two coffees. The next day, he paid $1.64 for two doughnuts and one coffee. How much does it cost for one doughnut and one coffee? \r
\n" ); document.write( "\n" ); document.write( "Thank you! \n" ); document.write( "
Algebra.Com's Answer #45719 by stanbon(75887)\"\" \"About 
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Write a system of two equations in two unknowns. Solve the system by using the addition method. « Mike paid $2.98 for three doughnuts and two coffees. The next day, he paid $1.64 for two doughnuts and one coffee. How much does it cost for one doughnut and one coffee?
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\n" ); document.write( "1st: 3d+2c=2.98
\n" ); document.write( "2nd: 2d+ c=1.64
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\n" ); document.write( "Multiply 2nd by 2 to get:
\n" ); document.write( "3rd: 4d+2c=3.28
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\n" ); document.write( "Subtract 1st from 3rd to get:
\n" ); document.write( "d=0.30 ( Cost of one doughnut)
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\n" ); document.write( "Substitute into 2nd to solve for c, as follows:
\n" ); document.write( "2(0.30)+c=1.64
\n" ); document.write( "c=1.04 (cost of one coffee)
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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