what is the value of the discriminant x^2-9
b^2 = 0
-4ac = -4(1)(-9) = 36
b^2-4ac = 36
note
sqrt (36) is 6
Small correction Damon:
the formula is
(-b + sqrt(b^2 - 4ac)) / 2a
-
Ans : + sqrt(36) / 2
-
ie + 6/2 and -6/3
Ans : + 3 and -3
Easier way: Method II
X^2 -9 = 0
X^2 = 9
X = Sqrt(9)
X = 3 or -3
Done!
To find the discriminant of the quadratic expression x^2 - 9, we can use the formula:
Discriminant = b^2 - 4ac.
For the given expression x^2 - 9, the quadratic equation can be written as ax^2 + bx + c, where a = 1, b = 0, and c = -9.
Substituting these values into the discriminant formula, we have:
Discriminant = (0)^2 - 4(1)(-9)
= 0 - (-36)
= 0 + 36
= 36.
Therefore, the discriminant of the expression x^2 - 9 is 36.