document.write( "Question 771917: Find the sum of all values of a such that the point (a,7) is 3 sqrt(5) from the point (2,1). \n" ); document.write( "

Algebra.Com's Answer #470549 by Cromlix(4381) $\"\"$ $\"About$

You can put this solution on YOUR website!
Using formula:
\n" ); document.write( "Square root of (x2 - x1)^2 + (y2 - y1)^2
\n" ); document.write( "Using (a, 7) and (2, 1)
\n" ); document.write( "Square root of(2 - a)^2 + (1 - 7)^2
\n" ); document.write( "Square root of (4 - 4a + a^2)+ (36)
\n" ); document.write( "Square root of (a^2 - 4a + 4 + 36)
\n" ); document.write( "Square root of a^2 - 4a + 40
\n" ); document.write( "Square root of a^2 - 4a + 40 = 3 sqrt(5)
\n" ); document.write( "Discarding square roots.
\n" ); document.write( "a^2 - 4a + 40 = 45 (sqrt(9*5))
\n" ); document.write( "a^2 - 4a - 5 = 0
\n" ); document.write( "(a + 1)(a - 5) = 0
\n" ); document.write( "a + 1 = 0
\n" ); document.write( "a = -1
\n" ); document.write( "a - 5 = 0
\n" ); document.write( "a = 5
\n" ); document.write( "These are the two values for a:
\n" ); document.write( "-1 and 5
\n" ); document.write( "Hope this helps.
\n" ); document.write( ":-) \n" ); document.write( "

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