document.write( "Question 118906: solve for x \"+x%5E2-6x-160=0+\" \n" ); document.write( "
Algebra.Com's Answer #87006 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given to solve:
\n" ); document.write( ".
\n" ); document.write( "\"+x%5E2-6x-160=0+\"
\n" ); document.write( ".
\n" ); document.write( "This equation can be solved by factoring. Look for factors of -160 that can be combined to
\n" ); document.write( "give -6. If you think about this -160 can be factored to -16 and + 10. If these two numbers
\n" ); document.write( "are added the result is -6. Using this information you can factor the left side of the equation
\n" ); document.write( "to get:
\n" ); document.write( ".
\n" ); document.write( "\"%28x+-+16%29%2A%28x+%2B+10%29+=+0\"
\n" ); document.write( ".
\n" ); document.write( "If you multiply out the two factors on left side you will get the given equation ... which is
\n" ); document.write( "as it should be.
\n" ); document.write( ".
\n" ); document.write( "If either of the factors is equal to zero, the equation will be true ... because a multiplication
\n" ); document.write( "by zero on the left side will make the entire left side equal to zero and therefore, the
\n" ); document.write( "left side will equal the zero on the right side.
\n" ); document.write( ".
\n" ); document.write( "So let's set each of the factors equal to zero and this will make the equation true.
\n" ); document.write( ".
\n" ); document.write( "First:
\n" ); document.write( ".
\n" ); document.write( "\"x+-+16+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Add 16 to both sides of this equation and you get for x:
\n" ); document.write( ".
\n" ); document.write( "\"x+=+16\"
\n" ); document.write( ".
\n" ); document.write( "Next set the other factor equal to zero:
\n" ); document.write( ".
\n" ); document.write( "\"+x+%2B+10+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Subtract 10 from both sides and you get:
\n" ); document.write( ".
\n" ); document.write( "\"x+=+-10\"
\n" ); document.write( ".
\n" ); document.write( "So you have two solutions for x ... x = 16 and x = -10. You can check these two answers by
\n" ); document.write( "returning to the original (given) equation and substituting each of these answers for
\n" ); document.write( "x to see if they make the left side of the equation become zero and therefore equal to the
\n" ); document.write( "right side.
\n" ); document.write( ".
\n" ); document.write( "The given equation is \"x%5E2+-+6x+-+160+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Letting x be 16 makes the left side:
\n" ); document.write( ".
\n" ); document.write( "\"16%5E2+-+6%2816%29+-+160+=+256+-+96+-+160+=+256+-+256+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Next let x be -10 makes the left side:
\n" ); document.write( ".
\n" ); document.write( "\"%28-10%29%5E2+-6%28-10%29+-+160+=+100+%2B+60+-+160+=+160+-+160+=+0\"
\n" ); document.write( ".
\n" ); document.write( "So for either value of x (16 and -10) the left side of the given equation becomes zero
\n" ); document.write( "and therefore equal to the right side of the equation ... making the equation true.
\n" ); document.write( ".
\n" ); document.write( "This means that the two answers we found are correct.
\n" ); document.write( ".
\n" ); document.write( "Hope this helps you to understand this problem and one way that it can be solved (factoring).
\n" ); document.write( ".
\n" ); document.write( "
\n" ); document.write( "
\n" );