document.write( "Question 87944: what is the distance between (-3,-2) and (1,4)\r
\n" ); document.write( "\n" ); document.write( "A) square root of 10
\n" ); document.write( "B) 27
\n" ); document.write( "C) 2 square root of 5
\n" ); document.write( "D) 18 square root of 3
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Algebra.Com's Answer #63842 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Something is wrong here.
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\n" ); document.write( "The distance between the two points is found by using the Pythagorean theorem. The change in
\n" ); document.write( "x values gives you one leg of the triangle, and the change in y values gives you the other
\n" ); document.write( "leg.
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\n" ); document.write( "Let's compute the change in x. In one of the points the x-value is -3. In the other point
\n" ); document.write( "the x-value is +1. So x goes from -3 to +1 and that is a distance of 4 units.
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\n" ); document.write( "Now let's compute the change in y. In one of the points the y-value is -2, and in the other
\n" ); document.write( "point it is +4. So y goes from -2 to +4 and that is a distance of 6 units.
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\n" ); document.write( "So we know that the two legs of the right triangle are 4 and 6. The hypotenuse of the
\n" ); document.write( "triangle is the distance between the points. The Pythagorean theorem tells us that the
\n" ); document.write( "sum of the squares of the two legs is the hypotenuse squared. In equation form this is:
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\n" ); document.write( "\"a%5E2+%2B+b%5E2+=+c%5E2\"
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\n" ); document.write( "where a is one of the legs, b is the other leg, and c is the distance we are looking for.
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\n" ); document.write( "Let's call a the x distance of 4 and b the y distance of 6. Substituting these values we
\n" ); document.write( "get:
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\n" ); document.write( "\"4%5E2+%2B+6%5E2+=+c%5E2\"
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\n" ); document.write( "and squaring out the terms on the left side results in:
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\n" ); document.write( "\"16+%2B+36+=+c%5E2\"
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\n" ); document.write( "Adding the terms on the left side simplifies the equation to:
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\n" ); document.write( "\"52+=+c%5E2\"
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\n" ); document.write( "Now solve for c by taking the square root of both sides to get:
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\n" ); document.write( "\"c+=+sqrt%2852%29+=+sqrt%284%2A13%29+=+sqrt%284%29%2Asqrt%2813%29+=+2%2Asqrt%2813%29\"
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\n" ); document.write( "If you use a calculator to find \"2%2Asqrt%2813%29\" you get \"2%2Asqrt%2813%29+=+7.211102551\".
\n" ); document.write( "So the distance between the two points you were given is 7.211102551 units.
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\n" ); document.write( "But none of your answers matches that value.
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\n" ); document.write( "Answer a) is square root of 10 and in your head you can tell that it has to be a little bigger
\n" ); document.write( "than square root of 9 which is 3 but it is less than the square root of 16 which is 4.
\n" ); document.write( "Therefore, answer a) is between 3 and 4, which means that it can't match our answer of
\n" ); document.write( "7.211102551.
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\n" ); document.write( "Answer b) is 27. That definitely doesn't match our answer.
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\n" ); document.write( "Answer c) is \"2%2Asqrt%285%29\" and you know that \"sqrt%285%29\" is less than \"sqrt%289%29\"
\n" ); document.write( "which is 3. So \"2%2Asqrt%285%29\" must be less than \"2%2A3\" and that means that answer c) is
\n" ); document.write( "less than 6. Therefore, it doesn't match our answer.
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\n" ); document.write( "Finally, Answer d) is \"18%2Asqrt%283%29\". You know that \"sqrt%283%29\" is greater than 1. If
\n" ); document.write( "it were just 1, then this answer would be \"18%2A1+=+18\". So this answer is greater than
\n" ); document.write( "18. Therefore, it can't be our answer of 7.211102551.
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\n" ); document.write( "None of the answers matches.
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\n" ); document.write( "Like I said at the beginning ... something is wrong here with this problem.
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\n" ); document.write( "Hope this helps you to see your way through the problem. The answer you are trying to
\n" ); document.write( "match (assuming that the points are correct) is \"2%2Asqrt%2813%29\".
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