Question

what is the value of the discriminant for the quadratic equation –3 = –x2 2x? discriminant = b2 – 4ac –8 4 8 16

Answer 1

x^2 - 2x - 3 = 0
d = b^2 - 4ac
d = (-2)^2 - 4 x 1 x (-3)
d = 4 + 12 = 16
d = 16

Answer 2

we know that

The formula to solve a quadratic equation of the form
`ax^(2) +bx+c=0` is equal to

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

the discriminant is equal to
`{b^(2)-4ac`

in this problem we have

`-3=-x^(2) +2x`

`x^(2)-2x-3=0`

so

`a=1\\b=-2\\c=-3`

substitute the values

`{(-2)^(2)-4(1)(-3)=4+12=16`

therefore

the answer is

`16`