F(x) = x(x + 7)(x + 2)

We can also find the vertex by using the expressions:

(

−

b

2

a

,

f

(

−

b

2

a

)

)

Standard form:

a

x

2

+

b

x

+

c

=

0

In this example,

a

=

−

1

and

b

=

0

x

=

−

0

2

(

−

1

)

=

0

2

=

0

y

=

f

(

0

)

=

7

−

0

2

=

7

Same result of

(

0

,

7

)

(202 bc - 220 ad) dynasty started by lui bang; a great and long-lasting rule, it discarded the harsh policies of the qin dynasty and adopted confucian principles; han rulers chose officials who passed the civil service exams rather than birth; it was a time of prosperity

the answer for 3 is b and the answer for 4 is d