Vertex Form
· (x,y) in the equation takes up a pair coordinate that lies on the parabola.
· (h,k) is the vertex.
· h tells whether to move left or right from the origin:
o if h is positive, then move h units to the left
o if h is negative, then move h units to the right
· k tells whether to move up or down from the origin:
o if k is positive, then move k units up
o if k is negative, then move k units down
· a tells whether the parabola is a vertical stretch or a compression.
o if a is greater than 1, the parabola is a positive vertical stretch.
· (h,k) is the vertex.
· h tells whether to move left or right from the origin:
o if h is positive, then move h units to the left
o if h is negative, then move h units to the right
· k tells whether to move up or down from the origin:
o if k is positive, then move k units up
o if k is negative, then move k units down
· a tells whether the parabola is a vertical stretch or a compression.
o if a is greater than 1, the parabola is a positive vertical stretch.
o if a is between 1 and -1, the parabola is a compression
o if a is lower than -1, than the parabola is a negative vertical stretch.
· y = a(x-h)^ 2 + k is graphed using the vertex.
o Plot the vertex (h,k)
o Go one unit horizontally and use the step formula each time.
§ Step formula: 1a, 3a, 5a…
o Connects dots in a U-shape.
o Plot the vertex (h,k)
o Go one unit horizontally and use the step formula each time.
§ Step formula: 1a, 3a, 5a…
o Connects dots in a U-shape.