document.write( "Question 84774: I have a question that I cannot work out. It is: Find the possible values of y if the points (-7,-9) and (-10, y) are a distance d=squareroot 178 apart. Hod do I do this? \n" ); document.write( "
Algebra.Com's Answer #61113 by ankor@dixie-net.com(22740)\"\" \"About 
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Find the possible values of y if the points (-7,-9) and (-10, y) are a distance d=squareroot 178 apart. Hod do I do this?
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\n" ); document.write( "Remember the distance formula:
\n" ); document.write( "d = \"sqrt%28%28x2-x1%29%5E2+%2B+%28y2-y1%29%5E2%29\"; In this problem: x1 = -7, x2 = -10; y1 = -9; y2 = y
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\n" ); document.write( "Substitute for x1, x2, y1, y2, and d
\n" ); document.write( "\"sqrt%28%28-10-%28-7%29%29%5E2+%2B+%28y-%28-9%29%29%5E2%29\" = \"sqrt%28178%29\"
\n" ); document.write( ":
\n" ); document.write( "\"sqrt%28%28-10%2B7%29%5E2+%2B+%28y%2B9%29%29%5E2%29\" = \"sqrt%28178%29\"
\n" ); document.write( ":
\n" ); document.write( "Squaring both sides gets rid of the radicals:
\n" ); document.write( "\"%28-10%2B7%29%5E2+%2B+%28y%2B9%29%5E2\" = 178
\n" ); document.write( ":
\n" ); document.write( "\"-3%5E2+%2B+%28y%5E2+%2B+18y+%2B+81%29\" = 178
\n" ); document.write( ":
\n" ); document.write( "y^2 + 18y + 81 + 9 - 178 = 0
\n" ); document.write( ":
\n" ); document.write( "y^2 + 18y - 88 = 0
\n" ); document.write( ":
\n" ); document.write( "Factors to:
\n" ); document.write( "(y + 22)(y - 4) = 0
\n" ); document.write( ":
\n" ); document.write( "y = +4 and y = -22
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\n" ); document.write( ":
\n" ); document.write( "you can check both solutions in the distance equation;
\n" ); document.write( "They should = \"sqrt%28178%29\" \n" ); document.write( "
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