Which is a zero of the quadratic function f(x) = 9x2 – 54x – 19?

Mathematics

1 answer:

liraira [26]3 years ago

7 0

Answer: Third Choice. x= 6 1/3

Step-by-step explanation:

Given

f(x) = 9x² - 54x - 19

Completing the square

3x -19

3x 1

Substitute back to the function

f(x) = (3x-19) (3x+1)

Simplify

x= 6 1/3 or -1/3

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