Given a quadratic function
y = 4x² - 19x - 5
or i will write it as
4x² - 19x - 5 = y
Zero of the function is when y have the value of zero.
So the quadratic equation will be
4x² - 19x - 5 = y
4x² - 19x - 5 = 0
Now make the equation to intercept form by factorization
4x² - 19x - 5 = 0
(4x + 1)(x - 5) = 0 (this is intercept form)
Solution 1
4x + 1 = 0
4x = -1
x = -1/4
Solution 2
x - 5 = 0
x = 5
SUMMARY
-1/4 and 5 are zero function of f(x) = 4x² - 19x - 5
