document.write( "Question 81771: Problem
\n" ); document.write( "Find three consecutive integers such that the sum of their squares is 77.
\n" ); document.write( "This is what I have, but not sure.
\n" ); document.write( "x^2 + x^2 + x^2 = 77 I don't know where to go from here. Thank you for your help.
\n" ); document.write( "

Algebra.Com's Answer #58599 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
The first thing to do is to let x be the first integer. Then the next consecutive integer
\n" ); document.write( "is 1 number higher or x + 1. And the next consecutive integer after that is (x+1) + 1 or
\n" ); document.write( "x + 2.
\n" ); document.write( ".
\n" ); document.write( "The squares of these numbers are:
\n" ); document.write( ".
\n" ); document.write( "\"%28x%5E2%29\"
\n" ); document.write( ".
\n" ); document.write( "\"%28x+%2B+1%29%5E2+=+x%5E2+%2B+2x+%2B+1\"
\n" ); document.write( ".
\n" ); document.write( "\"%28x+%2B+2%29%5E2+=+x%5E2+%2B+4x+%2B+4\"
\n" ); document.write( ".
\n" ); document.write( "If you add these three squares together you get:
\n" ); document.write( ".
\n" ); document.write( "\"x%5E2+%2B+x%5E2+%2B+2x+%2B+1+%2B+x%5E2+%2B+4x+%2B+4\"
\n" ); document.write( ".
\n" ); document.write( "Combine the like terms and you get:
\n" ); document.write( ".
\n" ); document.write( "\"3x%5E2+%2B%282+%2B+4%29x+%2B+%281+%2B+4%29\"
\n" ); document.write( ".
\n" ); document.write( "This reduces to:
\n" ); document.write( ".
\n" ); document.write( "\"3x%5E2+%2B+6x+%2B+5\"
\n" ); document.write( ".
\n" ); document.write( "This is the sum of the squares and the problem tells you that this sum equals 77. So
\n" ); document.write( "the equation becomes:
\n" ); document.write( ".
\n" ); document.write( "\"3x%5E2+%2B+6x+%2B+5+=+77\"
\n" ); document.write( ".
\n" ); document.write( "Put this into standard quadratic form by subtracting 77 from both sides to get:
\n" ); document.write( ".
\n" ); document.write( "\"3x%5E2+%2B+6x+-+72+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Since this is in standard quadratic form, you can solve it by using the quadratic
\n" ); document.write( "formula. Although it may be difficult to recognize, the left side of this equation can
\n" ); document.write( "be factored:
\n" ); document.write( ".
\n" ); document.write( "\"3%28x+-+4%29%28x+%2B+6%29+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Divide both sides by 3 to reduce the equation to:
\n" ); document.write( ".
\n" ); document.write( "\"%28x+-+4%29%28x+%2B+6%29+=+0\"
\n" ); document.write( ".
\n" ); document.write( "This equation will be true if one of the factors is zero because a multiplier of zero on the
\n" ); document.write( "left side will make the left side equal to zero, just as the right side is.
\n" ); document.write( ".
\n" ); document.write( "So solve this equation by setting each factor equal to zero.
\n" ); document.write( ".
\n" ); document.write( "\"x+-+4+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Solve by adding 4 to both sides to get \"x+=+4\". This would mean that the next two
\n" ); document.write( "consecutive integers are 5 and 6.
\n" ); document.write( ".
\n" ); document.write( "Now set the second factor equal to zero:
\n" ); document.write( ".
\n" ); document.write( "\"%28x+%2B+6%29+=+0\"
\n" ); document.write( ".
\n" ); document.write( "Solve by subtracting 6 from both sides to get \"x+=+-+6\". This makes the next two
\n" ); document.write( "consecutive integers (x+1 and x + 2) equal to -5 and -4.
\n" ); document.write( ".
\n" ); document.write( "So we have two possibilities. One solution is 4, 5, and 6. The other solution is -6, -5,
\n" ); document.write( "and -4.
\n" ); document.write( ".
\n" ); document.write( "Let's check them out.
\n" ); document.write( ".
\n" ); document.write( "\"4%5E2+%2B+5%5E2+%2B+6%5E2+=+16+%2B+25+%2B+36+=+77\"
\n" ); document.write( ".
\n" ); document.write( "That works. Now:
\n" ); document.write( ".
\n" ); document.write( "\"%28-6%29%5E2+%2B+%28-5%29%5E2+%2B+%28-4%29%5E2+=+36+%2B+25+%2B+16+=+77\"
\n" ); document.write( ".
\n" ); document.write( "Although it's a little more difficult to think about, -6, -5, and -4 are three consecutive
\n" ); document.write( "integers that also work.
\n" ); document.write( ".
\n" ); document.write( "Hope this helps you to understand the problem.
\n" ); document.write( "
\n" ); document.write( "
\n" );