document.write( "Question 477248: Please help me to solve those problems. I would really appreciate any help.Thanks!
\n" ); document.write( "1)There is a polynomial which, when multiplied by x^2+2x+3, gives 2x^5+3x^4+8x^3+8x^2+18x+9. What is that polynomial?
\n" ); document.write( "2)What are the coordinates of the points where the graphs of f(x) = x^3-x^2 + x + 1 and g(x) = x^3 + x^2 + x-1 intersect?
\n" ); document.write( "3)The polynomial f(x) has degree 2. If f(0) =-21, f(1) = -16, and f(2) = -9, then what are the x-intercepts of the graph of f?
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Algebra.Com's Answer #327177 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
1) Carry out long division of polynomial.
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\n" ); document.write( "\n" ); document.write( "2) Let \"x%5E3+-+x%5E2+%2B+x+%2B+1+=+x%5E3+%2B+x%5E2+%2B+x+-+1\"\r
\n" ); document.write( "\n" ); document.write( "==> \"2x%5E2+=+2\" ==> \"x%5E2+=+1\" ==> x = -1, 1
\n" ); document.write( "When x = -1, f(-1) = g(-1) = -2
\n" ); document.write( "When x = 1, f(1) = g(1) = 2
\n" ); document.write( "==> points of intersection are (-1,-2) and (1,2).\r
\n" ); document.write( "\n" ); document.write( "3) let \"f%28x%29+=+ax%5E2+%2B+bx+%2B+c\".
\n" ); document.write( "f(0) = -21 ==> c = -21.
\n" ); document.write( "f(1) = -16 ==> a + b - 21 = -16 ==> a+b = 5
\n" ); document.write( "f(-1) = -9 ==> 4a + 2b - 21 = -9 ==> 4a + 2b = 12 <==> 2a + b = 6.
\n" ); document.write( "Subtract the top equation from the bottom equation, to get a = 1
\n" ); document.write( "==> b = 4.
\n" ); document.write( "==> \"f%28x%29+=+x%5E2+%2B+4x+-21+=+%28x%2B7%29%28x-3%29\".
\n" ); document.write( "==> x-intercepts are (-7, 0) and (3,0).
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