document.write( "Question 36331: (1) find the x- intercepts of the graph of f(x) =2x^2-4x-4.\r
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\n" ); document.write( "\n" ); document.write( "(2) find all the vertical asymptotes for g(x) = x^2-4/x+2\r
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\n" ); document.write( "\n" ); document.write( "(3) find \"%28f%2Ag%29\"(x) if f(x) =3x-5 and g(x)x^2+1
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Algebra.Com's Answer #22260 by Nate(3500)\"\" \"About 
You can put this solution on YOUR website!
(1) find the x- intercepts of the graph of f(x) =2x^2-4x-4.
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-4x%2B-4+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-4%29%5E2-4%2A2%2A-4=48\".
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\n" ); document.write( " Discriminant d=48 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--4%2B-sqrt%28+48+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-4%29%2Bsqrt%28+48+%29%29%2F2%5C2+=+2.73205080756888\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-4%29-sqrt%28+48+%29%29%2F2%5C2+=+-0.732050807568877\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-4x%2B-4\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-4x%2B-4+=+2%28x-2.73205080756888%29%2A%28x--0.732050807568877%29\"
\n" ); document.write( " Again, the answer is: 2.73205080756888, -0.732050807568877.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-4%2Ax%2B-4+%29\"

\n" ); document.write( "\n" ); document.write( "(2) find all the vertical asymptotes for g(x)=(x^2-4)/(x+2)
\n" ); document.write( "\"g%28x%29=%28x%5E2-4%29%2F%28x%2B2%29\"
\n" ); document.write( "\"g%28x%29=%28%28x-2%29%28x%2B2%29%29%2F%28x%2B2%29\"
\n" ); document.write( "\"g%28x%29=%28x-2%29\" where the vertical asymptote is the deleted denominator \"x%2B2\"
\n" ); document.write( "so \"x%2B2\" is also expressed as: \"x=-2%29\" that is the vertical asymptote
\n" ); document.write( "In the line below, the point as (-2,-4) doesn't exist....
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Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation \"-1+x+%2B+1+y+=+-2\" describes a sloping line. For any
\n" ); document.write( " equation ax+by+c = 0, slope is \"-a%2Fb+=+--1%2F1\".
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. -2/-1 = 2.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is -2/1 = -2.
  • Slope is --1/1 = 1.
  • Equation in slope-intercept form: y=1*x+-2.
\"graph%28+500%2C+500%2C+2-8%2C+2%2B8%2C+-2-8%2C+-2%2B8%2C+1%2Ax%2B-2+%29+\"\n" ); document.write( "

\n" ); document.write( "\n" ); document.write( "(3) find \"%28f+of+g%29\"(x) if f(x) =3x-5 and g(x)x^2+1
\n" ); document.write( "Just plug in g(x) as 'x' for f(x)....
\n" ); document.write( "\"f%28x%29=3x-5\"
\n" ); document.write( "\"f%28x%29=3%28x%5E2%2B1%29-5\"
\n" ); document.write( "\"%28f+of+g%29%28x%29=3x%5E2-2\"
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