The Three Forms of Quadratic Equations:
Vertex Form
y  a ( x  h) 2  k
Standard Form
Intercept (Factored) Form
y  ax 2  bx  c
y  a( x  p)( x  q)
What does this form tell us?
What does this form tell us?
What does this form tell us?
 “a”
UP/DOWN
 “a”
UP/DOWN
 “a”
UP/DOWN
VERTICAL STRETCH/SHRINK
 “a”
 “a”
VERTICAL STRETCH/SHRINK
 “a”
VERTICAL STRETCH/SHRINK
 Vertex
(h, k)
You can “see” the vertex
in the equation
 Y-Intercept
(0, c)
You can “see” the y-intercept
in the equation
b
2a
You MUST find the vertex:
x
x
b
2a
then use the x-value to find the y-value
 x-Intercepts
(p, 0) & (q, 0)
You can “see” the x-intercepts
in the equation
You MUST find the vertex:
Average the x-intercepts by
x
pq
2
then use the x-value to find the y-value