document.write( "Question 836280: 7-sqrt(1-4x)-sqrt(4-6x)=0\r
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Algebra.Com's Answer #504068 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
This is a long and messy problem. The basic idea is this though: Isolate the square roots one by one on their own side. That will allow you to square both sides to eliminate each square root one by one. After doing all that, you can use the quadratic formula to solve for x. Remember to check ALL possible answers.\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281-4x%29-sqrt%284-6x%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281-4x%29=sqrt%284-6x%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%287-sqrt%281-4x%29%29%5E2=%28sqrt%284-6x%29%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"%287-sqrt%281-4x%29%29%287-sqrt%281-4x%29%29=4-6x\"\r
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\n" ); document.write( "\n" ); document.write( "\"7%287-sqrt%281-4x%29%29-sqrt%281-4x%29%287-sqrt%281-4x%29%29=4-6x\"\r
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\n" ); document.write( "\n" ); document.write( "\"49-7sqrt%281-4x%29-7sqrt%281-4x%29%2B%28sqrt%281-4x%29%29%5E2=4-6x\"\r
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\n" ); document.write( "\n" ); document.write( "\"49-7sqrt%281-4x%29-7sqrt%281-4x%29%2B1-4x=4-6x\"\r
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\n" ); document.write( "\n" ); document.write( "\"50-4x-14sqrt%281-4x%29=4-6x\"\r
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\n" ); document.write( "\n" ); document.write( "\"-14sqrt%281-4x%29=4-6x-50%2B4x\"\r
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\n" ); document.write( "\n" ); document.write( "\"-14sqrt%281-4x%29=-46-2x\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-14sqrt%281-4x%29%29%5E2=%28-46-2x%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"196%281-4x%29=%28-46-2x%29%28-46-2x%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"196%281-4x%29=-46%28-46-2x%29-2x%28-46-2x%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"196%281%29%2B196%28-4x%29=-46%28-46%29-46%28-2x%29-2x%28-46%29-2x%28-2x%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"196-784x=2116%2B92x%2B92x%2B4x%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=2116%2B92x%2B92x%2B4x%5E2-196%2B784x\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=4x%5E2%2B968x%2B1920\"\r
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\n" ); document.write( "\n" ); document.write( "\"4x%5E2%2B968x%2B1920=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"4%28x%5E2%2B242x%2B480%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B242x%2B480=0%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B242x%2B480=0\"\r
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\n" ); document.write( "\n" ); document.write( "Now use the quadratic formula to solve for x\r
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2%2B242%2Ax%2B480=0\" ( notice \"a=1\", \"b=242\", and \"c=480\")
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\n" ); document.write( " \"x+=+%28-242+%2B-+sqrt%28+%28242%29%5E2-4%2A1%2A480+%29%29%2F%282%2A1%29\" Plug in a=1, b=242, and c=480
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\n" ); document.write( " \"x+=+%28-242+%2B-+sqrt%28+58564-4%2A1%2A480+%29%29%2F%282%2A1%29\" Square 242 to get 58564
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\n" ); document.write( " \"x+=+%28-242+%2B-+sqrt%28+58564%2B-1920+%29%29%2F%282%2A1%29\" Multiply \"-4%2A480%2A1\" to get \"-1920\"
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\n" ); document.write( " \"x+=+%28-242+%2B-+sqrt%28+56644+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%28-242+%2B-+238%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%28-242+%2B-+238%29%2F2\" Multiply 2 and 1 to get 2
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%28-242+%2B+238%29%2F2\" or \"x+=+%28-242+-+238%29%2F2\"
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\n" ); document.write( " Lets look at the first part:
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\n" ); document.write( " \"x=%28-242+%2B+238%29%2F2\"
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\n" ); document.write( " \"x=-4%2F2\" Add the terms in the numerator
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\n" ); document.write( " \"x=-2\" Divide
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\n" ); document.write( " So one answer is
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\n" ); document.write( " \"x=-2\"
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\n" ); document.write( " Now lets look at the second part:
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\n" ); document.write( " \"x=%28-242+-+238%29%2F2\"
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\n" ); document.write( " \"x=-480%2F2\" Subtract the terms in the numerator
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\n" ); document.write( " \"x=-240\" Divide
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\n" ); document.write( " So another answer is
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\n" ); document.write( " \"x=-240\"
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\n" ); document.write( " So our solutions are:
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\n" ); document.write( " \"x=-2\" or \"x=-240\"
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\n" ); document.write( "So the *possible* solutions are \"x+=+-2\" or \"x+=+-240\"\r
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\n" ); document.write( "\n" ); document.write( "However, we must check them both\r
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\n" ); document.write( "\n" ); document.write( "Checking \"x+=+-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281-4x%29-sqrt%284-6x%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281-4%28-2%29%29-sqrt%284-6%28-2%29%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281%2B8%29-sqrt%284%2B12%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%289%29-sqrt%2816%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-3-4=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=0\" This is TRUE, so \"x+=+-2\" is definitely a solution.\r
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\n" ); document.write( "\n" ); document.write( "Checking \"x+=+-240\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281-4x%29-sqrt%284-6x%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281-4%28-240%29%29-sqrt%284-6%28-240%29%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%281%2B960%29-sqrt%284%2B1440%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-sqrt%28961%29-sqrt%281444%29=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"7-31-38=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"-62=0\" This is FALSE, so \"x+=+-240\" is NOT a solution.\r
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\n" ); document.write( "\n" ); document.write( "Final Answer: \"x+=+-2\"
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