document.write( "Question 1063423: Answer the question about the given function.\r
\n" ); document.write( "\n" ); document.write( "Given the function f(x) = x2 + 3x - 40, list the x-intercepts, if any, of the graph of f.
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Algebra.Com's Answer #678506 by rothauserc(4718)\"\" \"About 
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An x-intercept is where the graph of f(x) crosses the x axis, namely where the y coordinate is 0
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\n" ); document.write( "x^2 + 3x -40 = 0
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\n" ); document.write( "we can factor this quadratic into
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\n" ); document.write( "(x+8) * (x-5) = 0
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\n" ); document.write( "the x-intercepts occur at x = 5 and x = -8 and the x-intercept points are (5,0) and (-8,0)
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\n" ); document.write( "we can use the quadratic formula to solve for x, general form of a quadratic is
\n" ); document.write( "ax^2 +bx + c = 0
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\n" ); document.write( "x = (-3 + square root(3^2 - 4 * 1 * (-40)) / (2 * 1) = 5
\n" ); document.write( "x = (-3 - square root(3^2 - 4 * 1 * (-40)) / (2 * 1) = -8
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\n" ); document.write( "the graph of f(x) is
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\n" ); document.write( "\"+graph%28+300%2C+200%2C+-10%2C+10%2C+-50%2C+10%2C+x%5E2+%2B+3x+-40%29+\"
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