document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=104789>Question 104789</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/013052316X/algebrahomeworkh>Pretice hall mathematics. Algebra 1</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Your teacher is giving you a test worth 100 points containing 40 questions. There are two-point and four-point questions on the test. how many of each are on the test?\r<BR>\n" );
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document.write( "K what we have to do is write two linear equations and solve them, I have no idea how to do it so i need help please! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #76252 by </B><A HREF=/tutors/aboutme.mpl?userid=doukungfoo><B>doukungfoo(195)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=doukungfoo><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=doukungfoo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=76252\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x equal the number of two point questions and<BR>\n" );
document.write( "let y equal the number of four point questions<BR>\n" );
document.write( "now use the given information to write a system of equations<BR>\n" );
document.write( "Given: there are 40 questions on the test<BR>\n" );
document.write( "x + y = 40<BR>\n" );
document.write( "Given: There are two point and four point questions for a total of 100 points<BR>\n" );
document.write( "so 2 times the number of two point questions plus 4 times the number of four point questions equals 100 points<BR>\n" );
document.write( "2x + 4y = 100<BR>\n" );
document.write( "Now we have a system of equations we can use to solve for x and y<BR>\n" );
document.write( "take the first equation and set it equal to x<BR>\n" );
document.write( "x + y = 40<BR>\n" );
document.write( "x = 40 - y<BR>\n" );
document.write( "Now since we have shown that x equals 40 - y we can substitute that for x in the second equation<BR>\n" );
document.write( "2x + 4y = 100<BR>\n" );
document.write( "2(40-y) + 4y = 100<BR>\n" );
document.write( "now we have an equation with one variable that we can solve for<BR>\n" );
document.write( "lets do it<BR>\n" );
document.write( "2(40-y) + 4y = 100<BR>\n" );
document.write( "80 - 2y + 4y = 100<BR>\n" );
document.write( "80 + 2y = 100<BR>\n" );
document.write( "2y = 20<BR>\n" );
document.write( "y = 10<BR>\n" );
document.write( "Now you can use this value for y and solve for x in the first equation<BR>\n" );
document.write( "x + y = 40<BR>\n" );
document.write( "x + 10 = 40<BR>\n" );
document.write( "x = 30<BR>\n" );
document.write( "<B>Answers: so there are 10 four point questions and 30 two point questions</B><BR>\n" );
document.write( "Check these answers in both orginal equations:<BR>\n" );
document.write( "x + y = 40<BR>\n" );
document.write( "30 + 10 = 40<BR>\n" );
document.write( "40 = 40 <BR>\n" );
document.write( "That works now try the second equation<BR>\n" );
document.write( "2x + 4y = 100<BR>\n" );
document.write( "2(30) + 4(10) = 100<BR>\n" );
document.write( "60 + 40 = 100<BR>\n" );
document.write( "100 = 100<BR>\n" );
document.write( "Conclusion:<BR>\n" );
document.write( "They both work so we can be sure we have correctly solved the problem.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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