Factoring a Quadratic Expression into Two Binomials

Which of the following represents the factors of the expression  x² - 3x - 40 ?
A.)  (x - 8)(x + 5)
B.)  (x - 7)(x + 4)
C.)  (x + 10)(x - 4)
​D.)  (x + 6)(x - 9)

Factor the quadratic expression into two binomials.
The first terms of the two binomials are factors of x²......x and x
The second terms of the two binomials will multiply to get the constant term, -40, and add to get the middle coefficient, -3

x² - 3x - 40
=  (x - 8)(x + 5)   {factored into two binomials}

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