document.write( "Question 307358: I need to complete the pattern...HELP!!! Thanks so much for your help!\r
\n" ); document.write( "\n" ); document.write( "x.....y\r
\n" ); document.write( "\n" ); document.write( "1.....0
\n" ); document.write( "2.....2
\n" ); document.write( "4.....12
\n" ); document.write( "5......20
\n" ); document.write( "10....90
\n" ); document.write( "___....380
\n" ); document.write( "___....870
\n" ); document.write( "___....30
\n" ); document.write( "___....42\r
\n" ); document.write( "\n" ); document.write( "y = ______
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Algebra.Com's Answer #219880 by vksarvepalli(154)\"\" \"About 
You can put this solution on YOUR website!
General note:\r
\n" ); document.write( "\n" ); document.write( "keep it mind that in series or this type of function problems,first observe the question carefully,don't rush and start writing equations and all \r
\n" ); document.write( "\n" ); document.write( "if we get that pattern then its done.we can do also this problem by assuming it is a 2nd degree equation taking some constants and then substituting the given values and finding out the unknown constants.\r
\n" ); document.write( "\n" ); document.write( "like we can assume the relation to be y=ax^2+bx+c or y=ax^3+bx^2+cx+d since we got 5 pairs of x&y with us we can even go for a 4th degree equation,but imagine how tedious the problem becomes.\r
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\n" ); document.write( "\n" ); document.write( "so, here if we observe that \r
\n" ); document.write( "\n" ); document.write( "when x=1, y=0 that is lets say 1x0 or 1x(1-1)
\n" ); document.write( "when x=2, y=1 that may be say 2x1 or 2x(2-1)
\n" ); document.write( "when x=4, y=12 4x3 or 4x(4-1)\r
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\n" ); document.write( "\n" ); document.write( "by now we can say that the pattern is\r
\n" ); document.write( "\n" ); document.write( " \"y=x%28x-1%29+\" \r
\n" ); document.write( "\n" ); document.write( "put x=10 we get y= 90 which is verified.\r
\n" ); document.write( "\n" ); document.write( "so for y=380 x=20\r
\n" ); document.write( "\n" ); document.write( "20....380
\n" ); document.write( "30....870
\n" ); document.write( "6....30
\n" ); document.write( "7....42
\n" ); document.write( "
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