document.write( "Question 8481: how shall i find the square root of 169 without using calculator?? please describe briefly.. \n" ); document.write( "
Algebra.Com's Answer #4684 by bonster(299)\"\" \"About 
You can put this solution on YOUR website!
if you don't know it, think of the squared numbers that you already know and use them as markers...\r
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\n" ); document.write( "\n" ); document.write( "for example, you might already know that \"12%5E2\"=144 and you might already know that \"15%5E2\"=225. if so, you know that 169 would be between these numbers. so it would either be 13 or 14 \r
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\n" ); document.write( "\n" ); document.write( "Look at the ending...169 ends with a 9.
\n" ); document.write( "if we multiply by 4*4, the ending number will be 6 AND we also know that when we multiply even numbers, the ending number will NEVER end with an odd number like 9. \r
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\n" ); document.write( "\n" ); document.write( "We know that when we multiply 3*3, it ends in 9.
\n" ); document.write( "Then you know that 13*13 would be a good match.
\n" ); document.write( "\"13%5E2\"=169\r
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\n" ); document.write( "\n" ); document.write( "You can try to memorize some or just take an educated guess when playing with numbers.
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