document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=57306>Question 57306</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0131808540/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> The ordered pairs are for the same direct variation. Find each missing value.<BR>\n" );
document.write( "(-1,2) and (4,y)<BR>\n" );
document.write( "How would you do that?? would y be 7 because the difference between -1 and 2 is 3, and 4+3=7??? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #39011 by </B><A HREF=/tutors/aboutme.mpl?userid=funmath><B>funmath(2933)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=funmath><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=39011\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The ordered pairs are for the same direct variation. Find each missing value.<BR>\n" );
document.write( "(-1,2) and (4,y)<BR>\n" );
document.write( "If y varies directly as x, then y=kx.  k is the constant of variation.  <BR>\n" );
document.write( "We can use the first point to find out what k is so that we can solve for y in the second point.<BR>\n" );
document.write( "(x,y)=(-1,2) and y=kx substitute the x and y in and solve for k.<BR>\n" );
document.write( "2=k(-1)<BR>\n" );
document.write( "2=-k<BR>\n" );
document.write( "-(2)=-(-k)<BR>\n" );
document.write( "-2=k<BR>\n" );
document.write( "Therefore our equation is: y=-2x <BR>\n" );
document.write( "we can use this to solve for y in the second point.<BR>\n" );
document.write( "(x,y)=(4,y) and y=-2x substitute 4 in for x and solve for y.<BR>\n" );
document.write( "y=-2(4)<BR>\n" );
document.write( "y=-8<BR>\n" );
document.write( "Happy Calculating!!! </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );