Question

How do you find the zeros of:
f(x) = 9x^2 - 27x + 20

Answer 1

lets try this :
substitute
x= y + 3/2

see to it if you get it ..

Answer 2

Where did you get x=y+3/2 from?

Answer 3

Use the quadratic formula

Answer 4

-(-27) +_ sqrt(-27^2 -4(9)(20)/2(9)?

Answer 5

is that correct?

Answer 6

yes

Answer 7

\[9x^{2}-27x+20=0\]
\[x=\frac{-b \pm \sqrt{b^{2}-4ac}}{2a}\]
\[x=\frac{27 \pm \sqrt{729-720}}{18}\]
\[x=\frac{27 \pm \sqrt{9}}{18}\]
\[x=\frac{27 \pm 3}{18}\]

Answer 8

...5 and 4

-5 and -4

-5/3 and -4/3

5/3and 4/3?

Answer 9

\[x=\frac{30}{18}\]or \[x=\frac{24}{18}\]

Answer 10

\[x=\frac{5}{3}\]or \[x=\frac{4}{3}\]