document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=91498>Question 91498</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A line passing through (-8, 2) and (-1,y) is perpendicular to a line with  slope -7/5. Find the value of y.\r<BR>\n" );
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document.write( "I worked it out to be y=7.\r<BR>\n" );
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document.write( "Is this correct?\r<BR>\n" );
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document.write( "Thanks so much! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #66489 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=66489\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Your answer is correct!<BR>\n" );
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document.write( "Here's a brief description of a way you might have used.<BR>\n" );
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document.write( "Given that a line has a slope of -7/5. Its equation could be y = (-7/5)*x.<BR>\n" );
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document.write( "A line that is perpendicular to this line would have a slope that is the negative inverse of<BR>\n" );
document.write( "-7/5.  The negative inverse of this slope is +5/7. Therefore, in slope intercept form the <BR>\n" );
document.write( "equation of a line having a slope of +5/7 is:<BR>\n" );
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document.write( "y = (+5/7)x + b<BR>\n" );
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document.write( "From the problem you know that the point (-8,2) is satisfies this equation. If you substitute<BR>\n" );
document.write( "-8 for x and +2 for y, you can solve for b. After the substitutions, the equation becomes:<BR>\n" );
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document.write( "2 = (+5/7)*(-8) + b<BR>\n" );
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document.write( "Do the multiplication on the right side and you get:<BR>\n" );
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document.write( "2 = (-40/7) + b<BR>\n" );
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document.write( "Get rid of the -40/7 on the right side by adding + 40/7 to both sides and you get:<BR>\n" );
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document.write( "2 + 40/7 = b<BR>\n" );
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document.write( "Recognize that 2 is equal to 14/7. Substitute 14/7 for 2 and the equation is then:<BR>\n" );
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document.write( "14/7 + 40/7 = 54/7 = b<BR>\n" );
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document.write( "Return to our equation for the perpendicular line and substitute 54/7 for b to make the<BR>\n" );
document.write( "equation become:<BR>\n" );
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document.write( "y = (5/7)*x + 54/7<BR>\n" );
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document.write( "Now you can use this point to find the value of y in the point (-1, y). This point will<BR>\n" );
document.write( "be on the graph so when x is -1, we need to find the value of y from the equation.<BR>\n" );
document.write( "In the equation substitute -1 for x and the equation becomes:<BR>\n" );
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document.write( "y = (5/7)*(-1) + 54/7<BR>\n" );
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document.write( "Do the multiplication on the right side:<BR>\n" );
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document.write( "y = (-5/7) + 54/7<BR>\n" );
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document.write( "Add the two terms and you get:<BR>\n" );
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document.write( "y = 49/7 = 7<BR>\n" );
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document.write( "Your answer of 7 is correct.<BR>\n" );
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document.write( "Hope this shows you an understandable method that you might have used in solving your problem.<BR>\n" );
document.write( "If you used a different method (and there are other ways you might have used), maybe this<BR>\n" );
document.write( "method will help you to understand the problem a little more. Anyhow, good work! You used<BR>\n" );
document.write( "a method that worked! Cheers.  </SPAN>\n" );
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