document.write( "Question 875702: David entered a quiz. For each correct answer three points were added; for each incorrect answer one point was deducted.The quiz had 100 questions and David scored 176 points. How many questions did he answer correctly? \n" ); document.write( "
Algebra.Com's Answer #528397 by mananth(16946)\"\" \"About 
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correct answers be x
\n" ); document.write( "and wrong answers be y\r
\n" ); document.write( "\n" ); document.write( "x+y=100\r
\n" ); document.write( "\n" ); document.write( "3x-y=176\r
\n" ); document.write( "\n" ); document.write( "x= number of correct answers
\n" ); document.write( "y= number of wrong answers
\n" ); document.write( "
\n" ); document.write( "1 x + 1 y = 100 .............1
\n" ); document.write( "
\n" ); document.write( "3 x -1 y = 176 .............2
\n" ); document.write( "Eliminate y
\n" ); document.write( "multiply (1)by 1
\n" ); document.write( "Multiply (2) by 1
\n" ); document.write( "1 x 1 y = 100
\n" ); document.write( "3 x -1 y = 176
\n" ); document.write( "Add the two equations
\n" ); document.write( "4 x = 276
\n" ); document.write( "/ 4
\n" ); document.write( "x = 69
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "1 x + 1 y = 100
\n" ); document.write( "69 + y = 100
\n" ); document.write( " y = 100 -69
\n" ); document.write( " y = 31
\n" ); document.write( " y = 31
\n" ); document.write( "x= 69 number of correct answers
\n" ); document.write( "y= 31 number of wrong answers
\n" ); document.write( "m.ananth@hotmail.ca
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