document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1031482>Question 1031482</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Why is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=49y%5E2%2B16 ALIGN=MIDDLE  ALT=\"49y%5E2%2B16\"   DISABLED_style= \"max-width:90%; height:auto;\" > prime, but <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16y%5E2-49 ALIGN=MIDDLE  ALT=\"16y%5E2-49\"   DISABLED_style= \"max-width:90%; height:auto;\" > isn't? Any tips on how I can tell if a polynomial is prime or not? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #646174 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=646174\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I assume by a prime polynomial you mean \"factorable over the integers.\"\r<BR>\n" );
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document.write( "16y^2 - 49 is factorable since it is the difference of two squares, and can be written as (4y-7)(4y+7). But 49y^2 + 16 can't be factored over integers.\r<BR>\n" );
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document.write( "In general, determining whether a polynomial is factorable over integers is difficult, but sometimes you may be able to look for patterns, or find roots of the polynomial, etc. </SPAN>\n" );
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