Answer:
f(t) = 2(2t - 1)(5t + 6)
Explanation:
We are given a quadratic equation and we have to convert it into factored from. For this purpose we will do factorization.
f(t) = 20t^2 + 14t - 12
first take 2 as common from the right hand side of equation
f(t) = 2(10t² + 7t - 6)
We can break the midterm (+7t) in two terms such that when they are multiplied the result is -60 i.e. equal to product of first and third term of the equation above.

Taking 5t+6 as common above
f(t) = 2(2t - 1)(5t + 6)