Question

Calculate the value

of the unknown
coefficient b of a
quadratic equation
when the
discriminant of that
equation is known.

3x² + bx + 2 = 0; Coefficient = 12

​

Answer 1

The value of b is either + 6 or -6

Explanation:

Here, given that we have the value for the discriminant, we want to calculate the value for the coefficient of x

mathematically, the discriminant can be calculated using the equation;

D = b^2 - 4ac

a represents the coefficient of x^2 which is 3

b represents the coefficient of x given as b

2 represents the last number

D is the discriminant = 12

So we have that;

12 = b^2 - 4(3)(2)

12 = b^2 - 24

b^2 = 24 + 12

b^2 = 36

b = √36

b = +6 or -6