f(x) = 3x^2 - 11x -20
To find the zeros of the function, first we factor the expression as follows:
f(x) = (3x + 4)(x - 5)
Now we equal the expression to zero:
(3x + 4)(x - 5) = 0
If the expression is equal to zero, that means at least one of the factors is equal to zero, so:
3x + 4 = 0, then x = - 4/3
or
x - 5 = 0, then x = 5
The zeros of the function are:
(-4/3, 0) and (5, 0)
