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Key Terms

axis of symmetry
The axis of symmetry is the vertical line passing through the middle of the parabola y=ax2+bx+c.y=ax2+bx+c.
completing the square
Completing the square is a method used to solve quadratic equations.
consecutive even integers
Consecutive even integers are even integers that follow right after one another. If an even integer is represented by nn, the next consecutive even integer is n+2n+2, and the next after that is n+4n+4.
consecutive odd integers
Consecutive odd integers are odd integers that follow right after one another. If an odd integer is represented by nn, the next consecutive odd integer is n+2n+2, and the next after that is n+4n+4.
discriminant
In the Quadratic Formula, x=b±b24ac2ax=b±b24ac2a the quantity b24acb24ac is called the discriminant.
parabola
The graph of a quadratic equation in two variables is a parabola.
quadratic equation
A quadratic equation is an equation of the form ax2+bx+c=0ax2+bx+c=0, where a0.a0.
quadratic equation in two variables
A quadratic equation in two variables, where a,b,andca,b,andc are real numbers and a0a0 is an equation of the form y=ax2+bx+c.y=ax2+bx+c.
Square Root Property
The Square Root Property states that, if x2=kx2=k and k0k0, then x=korx=k.x=korx=k.
vertex
The point on the parabola that is on the axis of symmetry is called the vertex of the parabola; it is the lowest or highest point on the parabola, depending on whether the parabola opens upwards or downwards.
x-intercepts of a parabola
The x-intercepts are the points on the parabola where y=0.y=0.
y-intercept of a parabola
The y-intercept is the point on the parabola where x=0.x=0.
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