document.write( "Question 1090512: Hi can someone please help me answer this question? thanks so much\r
\n" ); document.write( "\n" ); document.write( "Describe three ways to determine the zeros of the quadratic function f(x)=-3x^2+27x-42. Solve for the zeros for each method. \n" ); document.write( "
Algebra.Com's Answer #704967 by Boreal(15235)\"\" \"About 
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f(x)=-3x^2+27x-42.
\n" ); document.write( "factor -3(x^2-9x+14)=-3(x-7)(x-2)=0, and x=7, 2
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\n" ); document.write( "complete the square after first changing all signs to 3x^2-27x+42=0 and move the constant so that 3x^2-27x=-42
\n" ); document.write( "divide the left side by 3 to get 3(x^2-9x) and complete the square by taking half of -9 and squaring it to get 20.25; X^2-9X+20.25=-42+3(20.25)
\n" ); document.write( "add 60.75 to the right because of the 3
\n" ); document.write( "now it is 3(x-4.5)^2=18.75
\n" ); document.write( "Divide by 3
\n" ); document.write( "(x-4.5)^2=6.25
\n" ); document.write( "take the square root.
\n" ); document.write( "x-4.5=+/- 2.5
\n" ); document.write( "x=7, 2
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\n" ); document.write( "graph it
\n" ); document.write( "\"graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C-3x%5E2%2B27x-42%29\"\r
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