# a.complete the square to write the quadratic equation f(x)-3x^2+6x+5 in standard form

• Mar 9th 2010, 07:40 AM
Mhockey02
a.complete the square to write the quadratic equation f(x)-3x^2+6x+5 in standard form
b. Identify the vertex of the parabola
c. State the equation of the axis of symmetry.
d. Factor or use the quadratic formula to find the x-intercepts of the graph, if any.
• Mar 9th 2010, 08:30 AM
HallsofIvy
??? You want someone to do the problem for you?

What have you done on this problem yourself?

Have you completed the square in \$\displaystyle f(x)= 3x^2+ 6x+ 5\$?.

I will give you a hint to start: write it as \$\displaystyle f(x)= 3(x^2+ 2x )+ 5\$ and complete the square in the parentheses.
• Mar 9th 2010, 08:35 AM
Mhockey02
I found the vertex of the parabola and stated the equation of the axis of symmetry and sketched the graph. Having trouble with completing the square and factoring or using the quadratic formula to find the x-intercepts. I know there are 2 x intercepts.
• Mar 10th 2010, 08:33 AM
HallsofIvy
\$\displaystyle f(x)= 3x^2+ 6x+ 5= 3(x^2+ 2x+ )+ 5\$

What do you need to add (and subtract) to make the expression in the parentheses a perfect square?