document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=30475>Question 30475</A>: <I><SPAN STYLE=\"word-break: break-all;\"> (7) Question:<BR>\n" );
document.write( "Solve for y: -2y-2=sqrt2y^2-7-7. You many include extraneous solutions.\r<BR>\n" );
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document.write( "(a) 2, 8<BR>\n" );
document.write( "(b) -2,8<BR>\n" );
document.write( "(c) -2, -8<BR>\n" );
document.write( "(d) 2, -8\r<BR>\n" );
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document.write( "Please be specific as to which letter answer is correct. Thanks! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #17347 by </B><A HREF=/tutors/aboutme.mpl?userid=sdmmadam@yahoo.com><B>sdmmadam@yahoo.com(530)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sdmmadam@yahoo.com><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=17347\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If the given problem is <BR>\n" );
document.write( "-2y-2 =sqrt(2y^2-7)-7  ----(1)<BR>\n" );
document.write( "-2y-2+7 = sqrt(2y^2-7)<BR>\n" );
document.write( "-2y+5 = sqrt(2y^2-7)<BR>\n" );
document.write( "Squaring both the sides<BR>\n" );
document.write( "(5-2y)^2 = (2y^2-7)   <BR>\n" );
document.write( "[by additive commutativity -2y+5 = 5-2y and using [sqrt(p)]^2 = p ]<BR>\n" );
document.write( "25+4y^2-20y = 2y^2-7  (using (a-b)^2 = a^2+b^2-2ab and here a = 5 and b = 2y )<BR>\n" );
document.write( "(4y^2-2y^2)-20y+25+7 = 0 (grouping like terms,changing sign while changing side)<BR>\n" );
document.write( "2y^2-20y+32 = 0<BR>\n" );
document.write( "dividing by 2<BR>\n" );
document.write( "y^2-10y+16 =0<BR>\n" );
document.write( "y^2-8y-2y+16 = 0<BR>\n" );
document.write( "(since sum is -10 and product is 16, the two terms into which the middle term is split are -8y and -2y so that -10y = (-8y)+(-2y) <BR>\n" );
document.write( "and (-8y)X(-2y) = 16y^2 = (y^2)X(16) )<BR>\n" );
document.write( "y(y-8)-2(y-8) = 0<BR>\n" );
document.write( "yp-2p = 0 where p= (y-8)<BR>\n" );
document.write( "p(y-2) =0<BR>\n" );
document.write( "(y-8)(y-2) = 0<BR>\n" );
document.write( "(y-8) = 0 gives y = 8<BR>\n" );
document.write( "and (y-2) = 0 gives y = 2<BR>\n" );
document.write( "Answer: y = 2 and y = 8<BR>\n" );
document.write( "which is your choice (a) 2,8\r<BR>\n" );
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document.write( " </SPAN>\n" );
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