document.write( "Question 422841: I do not fully understand radical expressions like 7 times the square root of 12. How exactly do you find the answer and is there a good way for me to check my answer on paper or with a calculator? \r
\n" ); document.write( "\n" ); document.write( "Also how do you add and subtract them to get answers with a number outside a square root like 6 times the square root of 54 or something. \r
\n" ); document.write( "\n" ); document.write( "One more question. When there are letters and numbers with the variable is it any different to solve. For example the square root of 128n^17 \r
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\n" ); document.write( "\n" ); document.write( "Help would be much appreciated! Im trying to learn all this without a teacher.
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Algebra.Com's Answer #295084 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
I do not fully understand radical expressions like 7 times the square root of 12.
\n" ); document.write( "Taking your example \"7sqrt%2812%29\"
\n" ); document.write( "Factor 12 in a way the reveals at perfect square
\n" ); document.write( "\"7sqrt%284%2A3%29\"
\n" ); document.write( "Extract the square root of 4, which is 2
\n" ); document.write( "\"7%2A2sqrt%283%29\" = \"14sqrt%283%29\", no further action can be taken
\n" ); document.write( ":
\n" ); document.write( "Check this on a calc: enter 7*\"sqrt%2812%29\" to get 24.2487..
\n" ); document.write( "Then enter your solution: 14*\"sqrt%283%29\" to get 24.2487.., the same if you did it right.
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Also how do you add and subtract them to get answers with a number outside a square root like 6 times the square root of 54 or something.
\n" ); document.write( ":
\n" ); document.write( "You can add and subtract only like terms, For example \"3sqrt%282%29\" + \"2sqrt%282%29\" = \"5sqrt%282%29\"
\n" ); document.write( "but \"3sqrt%282%29\" + \"2sqrt%283%29\" are not like terms and can't be added
\n" ); document.write( ":
\n" ); document.write( "However, after simplifying they may be like terms, this example
\n" ); document.write( "\"2sqrt%286%29\" + \"6sqrt%2854%29\"
\n" ); document.write( "Factor 54 to reveal a perfect square
\n" ); document.write( "\"2sqrt%286%29\" + \"6sqrt%289%2A6%29\"
\n" ); document.write( "Extract the square root of 9
\n" ); document.write( "\"2sqrt%286%29\" + \"6%2A3sqrt%286%29\" = \"2sqrt%286%29\" + \"18sqrt%286%29\" =
\n" ); document.write( "now they are like terms so we have: \"20sqrt%286%29\"\r
\n" ); document.write( "\n" ); document.write( ":
\n" ); document.write( "One more question. When there are letters and numbers with the variable is it any different to solve. For example the square root of 128n^17
\n" ); document.write( ":
\n" ); document.write( "Using \"sqrt%28128n%5E17%29\" we can factor to reveal perfect squares
\n" ); document.write( "\"sqrt%2864%2A2%2An%5E16%2An%29\"
\n" ); document.write( "remember the sqrt of n^16 is n^8 (n^8*n^8), so we have
\n" ); document.write( "\"8%2An%5E8%2Asqrt%282n%29\"
\n" ); document.write( ":
\n" ); document.write( "We treat variables the same way, just remember the law of exponents.
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