Answer:
Your answers would be:
x = 10 and x = -8
Step-by-step explanation:
Solve for the zeros:
x² - 2x - 78 = 2
Subtract both sides by 2.
x² - 2x - 80 = 0
Use the quadratic formula: [tex]x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
a = 1
b = -2
c = -80
Plug in and solve:
[tex]x=\frac{-(-2)\pm\sqrt{(-2)^2-4(1)(-80)}}{2(1)}\\\\x=\frac{2\pm\sqrt{(-2)^2-4(1)(-80)}}{2(1)}\\\\x=\frac{2\pm\sqrt{4-4(-80)}}{2(1)}\\\\x=\frac{2\pm\sqrt{4+320}}{2(1)}\\\\x=\frac{2\pm\sqrt{324}}{2(1)}\\\\x=\frac{2\pm18}{2}\\[/tex]
Solve for +:
[tex]x=\frac{2+18}{2}\\\\x=\frac{20}{2}\\\\x=10[/tex]
Solve for -:
[tex]x=\frac{2-18}{2}\\\\x=\frac{-16}{2}\\\\x=-8[/tex]
