document.write( "Question 842482: How does one solve this equation?
\n" ); document.write( "(√10+(3√x)) = (√x)\r
\n" ); document.write( "\n" ); document.write( "The radical over the 10 covers the whole equation on the left side of the equals sign.\r
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Algebra.Com's Answer #507567 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
if i understand you correctly, your equation is:\r
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\n" ); document.write( "\n" ); document.write( "sqrt(10 + 3 * sqrt(x)) = sqrt(x)\r
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\n" ); document.write( "\n" ); document.write( "pushing this through the algebra.com equation generator make it look like this:\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2810+%2B+3+%2A+sqrt%28x%29%29+=+sqrt%28x%29\"\r
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\n" ); document.write( "\n" ); document.write( "start with:
\n" ); document.write( "sqrt(10 + 3 * sqrt(x)) = sqrt(x)
\n" ); document.write( "square both sides of this equation to get:
\n" ); document.write( "10 + 3 * sqrt(x) = x
\n" ); document.write( "subtract 10 from both sides of the equation and subtract 3*sqrt(x) from both sides of the equation to get:
\n" ); document.write( "0 = x - 3*sqrt(x) - 10
\n" ); document.write( "commute this to get:
\n" ); document.write( "x - 3*sqrt(x) - 10 = 0
\n" ); document.write( "this is a quadratic equation in disguised form.
\n" ); document.write( "let y = sqrt(x) and this equation becomes:
\n" ); document.write( "y^2 - 3*y - 10 = 0
\n" ); document.write( "factor this equation to get:
\n" ); document.write( "(y-5) * (y+3) = 0
\n" ); document.write( "solve for y to get:
\n" ); document.write( "y = 5 or y = -3
\n" ); document.write( "replace y with sqrt(x) to get:
\n" ); document.write( "sqrt(x) = 5 or sqrt(x) = -3
\n" ); document.write( "solve for x to get:
\n" ); document.write( "x = 25 or x = 9
\n" ); document.write( "now you need to check to see if these solutions are good by replacing x in the original equation with these values of x to see if the equations hold true.\r
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\n" ); document.write( "\n" ); document.write( "first we'll do 25.
\n" ); document.write( "the original equation is:
\n" ); document.write( "sqrt(10 + 3 * sqrt(x)) = sqrt(x)
\n" ); document.write( "replace x with 25 to get:
\n" ); document.write( "sqrt(10 + 3 * sqrt(25)) = sqrt(25)
\n" ); document.write( "simplify to get:
\n" ); document.write( "sqrt(10 + 3*5) = 5
\n" ); document.write( "simplify further to get:
\n" ); document.write( "sqrt(25) = 5
\n" ); document.write( "simplify further to get:
\n" ); document.write( "5 = 5
\n" ); document.write( "the equation is true so x = 25 is a good solution.\r
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\n" ); document.write( "\n" ); document.write( "now we'll do 9.
\n" ); document.write( "the original equation is:
\n" ); document.write( "sqrt(10 + 3 * sqrt(x)) = sqrt(x)
\n" ); document.write( "replace x with 9 to get:
\n" ); document.write( "sqrt(10 + 3 * sqrt(9)) = sqrt(9)
\n" ); document.write( "simplify to get:
\n" ); document.write( "sqrt(10 + 3*3) = 3
\n" ); document.write( "simplify to get:
\n" ); document.write( "sqrt(19) = 3
\n" ); document.write( "this is not true, so x = -3 cannot be a good solution.\r
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\n" ); document.write( "\n" ); document.write( "the problem is that the square root of (9) is not equal to -3.
\n" ); document.write( "it is equal to 3.
\n" ); document.write( "the square root of a number is always the positive root, unless you are solving for y^2.
\n" ); document.write( "example:
\n" ); document.write( "if your equation is y^2 = 9, then y = +/- sqrt(9) = +/- 3
\n" ); document.write( "sqrt(9) can be + 3 or it can be - 3 because you are solving for y^2.
\n" ); document.write( "if your equation is y = sqrt(9), however, then y = + 3 only.\r
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\n" ); document.write( "\n" ); document.write( "the grpah of your 2 equations is shown below.
\n" ); document.write( "they are equal when the graph of the equations intersect.
\n" ); document.write( "the 2 equations to be graphed are:
\n" ); document.write( "y = sqrt(10 + 3*sqrt(x))
\n" ); document.write( "y = sqrt(x)
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\n" ); document.write( "you can see that the graphs intersect at x = 25 and y = 5 which is the coordinate point of (25,5).\r
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