Answer:
B. x² - 3x - 40
Step-by-step explanation:
The factored form of quadratic function:
[tex]y=a(x-x_1)(x-x_2)[/tex]
where x₁ and x₂ are the roots of the quadratic function and the solutions of the corresponding quadratic equation.
We have x₁ = 8 and x₂ = -5. Substitute:
[tex]y=a(x-8)(x-(-5))[/tex]
[tex]y=a(x-8)(x+5)[/tex] use FOIL: (a + b)(c + d) = ac + ad + bc + bd
[tex]y=a[(x)(x)+(x)(5)+(-8)(x)+(-8)(5)][/tex]
[tex]y=a(x^2+5x-8x-40)[/tex]
[tex]y=a(x^2-3x-40)[/tex]
For a = 1 we have the equation:
B. x² - 3x - 40
