2
STANDARD FORM OF A QUADRATIC:
f(x) = ax
+ bx + c
Put f(x) above into VERTEX FORM by completing the square (fill in the blanks):
2
STEP 1:
f(x) = a(x
+ _____ x ) + c
2
STEP 2:
f(x) = a(x
+ ______ x + ______ ) + c - _______
2
STEP 3:
f(x) = a ( x + _______ )
+ __________
Based on the vertex form you wrote in
Step 3, what formula could you use to
find the x-coordinate of the vertex of a
quadratic function’s graph?
NOW, use what you learned to Find the x-coordinate of the vertex of:
2
f(x) = x
– 5x + 3
2
f(x) = 2x
+ 4x + 9
2
f(x) = -2x
+ 7x – 3