Answer:
Step-by-step explanation:
Hello,
c= -4 * 2 = -8 as
[tex]x^2+bx+c=(x+4)(x-2)=x^2+2x-8[/tex]
with the quadratic formula
[tex]x_1=\dfrac{-b+\sqrt{b^2-4ac}}{2a}\\\\x_2=\dfrac{-b-\sqrt{b^2-4ac}}{2a}[/tex]
And
[tex]x_1x_2=\dfrac{b^2-b^2+4ac}{4a^2}=\dfrac{c}{a}[/tex]
thanks
