Question

Which shows the correct substitution of the values a, b, and c from the equation –2 = –x + x2 – 4 into the quadratic formula?

Answer 1

$x= \frac{-b+/- \sqrt{b^2-4ac} }{2a}$

first solve for 0=ax^2+bx+c
-2=-x+x^2-4
add 2 to both sides
0=x^2-x-2
a=1
b=-1
c=-2

$x= \frac{-(-1)+/- \sqrt{(-1)^2-4(1)(-2)} }{2(1)}$

last one is answer

Answer 2

The correct answer is D. on edg