document.write( "Question 32364This question is from textbook Elementary and Intermediate alegbra
\n" ); document.write( ": I need help solving x4 -5x2 - 36=0 I am not sure what to do with x4 \n" ); document.write( "

Algebra.Com's Answer #18873 by Cintchr(481) $\"\"$ $\"About$

You can put this solution on YOUR website!
First, always try and solve by factoring. This one happens to be factorable.
\n" ); document.write( " $\"+x%5E4+-5x%5E2+-+36=0+\"$
\n" ); document.write( "-9 * 4 = 36 and -9 + 4 = -5
\n" ); document.write( " $\"+%28x%5E2+-9%29%28x%5E2+%2B+4%29+=0+\"$
\n" ); document.write( "Continue factoring
\n" ); document.write( " $\"+%28x-3%29%28x%2B3%29%28x%5E2%2B4%29=0+\"$
\n" ); document.write( "Set each piece equal to zero
\n" ); document.write( " $\"+x-3=0+\"$ and $\"+x%2B3+=+0+\"$ and $\"+x%5E2%2B4=0+\"$
\n" ); document.write( " $\"+x=3+\"$ and $\"+x=-3+\"$ and $\"+x%5E2+=+-4+\"$
\n" ); document.write( " $\"+x=3+\"$ and $\"+x=-3+\"$ and $\"+sqrt%28x%5E2%29+=+sqrt%28-4%29+\"$
\n" ); document.write( " $\"+x=3+\"$ and $\"+x=-3+\"$ and $\"+x+=+sqrt%28-4%29+\"$
\n" ); document.write( " $\"+x=3+\"$ and $\"+x=-3+\"$ and $\"+x+=+i%28sqrt%284%29%29+\"$
\n" ); document.write( " $\"+x=3+\"$ and $\"+x=-3+\"$ and $\"+x+=+2i+\"$
\n" ); document.write( "assuming your instructor wants ONLY real roots, then x = {3, -3 }
\n" ); document.write( "If s/he wants all roots ... x = { -3, 3, 2i } \n" ); document.write( "

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