Question

Find the zeros of the function. f(x) = 9x2 - 27x + 20

Answer 1

use quadratic formula

u'll get x= (27+3)/2*9 and (27-3)/2*9

x=5/3 and 4/3

Answer 2

The zeros of the function are
`(5)/(3)` and
`(4)/(3)`.

Explanation:

The given function is

`f(x)=9x^2-27x+20`

Equate f(x)=0 to find the zeroes of the function.

`9x^2-27x+20=0`

Using splitting the middle terms method, the middle term can be written as -15x-12x.

`9x^2+(-15x-12x)+20=0`

`(9x^2-15x)+(-12x+20)=0`

Taking out common factors from each parenthesis.

`3x(3x-5)-4(3x-5)=0`

`(3x-5)(3x-4)=0`

Using zero product property, we get

`3x-5=0\Rightarrow x=(5)/(3)`

`3x-4=0\Rightarrow x=(4)/(3)`

Therefore the zeros of the function are
`(5)/(3)` and
`(4)/(3)`.