document.write( "Question 948333: given f(x)=2x^2+5x+3.
\n" ); document.write( "a) the y-intercept
\n" ); document.write( "b) the x-intercept, if any
\n" ); document.write( "c) the vertex
\n" ); document.write( "

Algebra.Com's Answer #578848 by macston(5194)\"\" \"About 
You can put this solution on YOUR website!
f(x)=2x^2+5x+3
\n" ); document.write( "Section A: Y-intercept
\n" ); document.write( "The y-intercept is the y value(s) where x=0
\n" ); document.write( "In this case:
\n" ); document.write( "\"y=2%280%5E2%29%2B5%280%29%2B3\"
\n" ); document.write( "\"y=3\" ANSWER A The y-intercept is (0,3)
\n" ); document.write( "Section B: X-intercept
\n" ); document.write( "The graph intercepts the x axis when the y value is 0, so:
\n" ); document.write( "\"2x%5E2%2B5x%2B3=0\"
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B5x%2B3+=+0\") has the following solutons:
\n" ); document.write( "
\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
\n" ); document.write( "
\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
\n" ); document.write( "
\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%285%29%5E2-4%2A2%2A3=1\".
\n" ); document.write( "
\n" ); document.write( " Discriminant d=1 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-5%2B-sqrt%28+1+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"x%5B1%5D+=+%28-%285%29%2Bsqrt%28+1+%29%29%2F2%5C2+=+-1\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%285%29-sqrt%28+1+%29%29%2F2%5C2+=+-1.5\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"2x%5E2%2B5x%2B3\" can be factored:
\n" ); document.write( " \"2x%5E2%2B5x%2B3+=+2%28x--1%29%2A%28x--1.5%29\"
\n" ); document.write( " Again, the answer is: -1, -1.5.\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%2B5%2Ax%2B3+%29\"

\n" ); document.write( "\n" ); document.write( "Thus the x-intercepts are at -1 and -1.5 or
\n" ); document.write( "ANSWER B: X=intercepts are at (-1,0) and (-1.5,0).
\n" ); document.write( "Section C: Vertex
\n" ); document.write( "Given equation of form:
\n" ); document.write( "\"f%28x%29=Ax%5E2%2BBx%2BC\"
\n" ); document.write( "the axis of symmetry (x value of vertex) is given by:
\n" ); document.write( "\"x=%28%28-B%29%2F2A%29\"
\n" ); document.write( "In this case:
\n" ); document.write( "\"x=%28%28-5%29%2F2%282%29%29\"=\"-5%2F4\"
\n" ); document.write( "Use this x value in the equation to find y value of vertex
\n" ); document.write( "\"y=2%28-5%2F4%29%5E2%2B5%28-5%2F4%29%2B3\"
\n" ); document.write( "\"y=2%2825%2F16%29-%2825%2F4%29%2B3\"
\n" ); document.write( "\"y=%2825%2F8%29-%2825%2F4%29%2B3\"
\n" ); document.write( "\"y=-25%2F8%2B24%2F8\"=\"-1%2F8\" ANSWER C: The vertex is at (-5/4,-1/8)
\n" ); document.write( "This graph shows the vertex more clearly, with x- and y- intercepts:
\n" ); document.write( "\"+graph%28+800%2C+800%2C+-5%2C+5%2C+-5%2C+5%2C+2x%5E2%2B5x%2B3%29+\"
\n" ); document.write( "
\n" );