Answer:
D = 41
Explanation:
y = ax² + bx + c
The discriminant D = b² - 4ac tells the types of roots the equation has.
If D < 0 , then quadratic equation has no real roots, has two imaginary roots.
If D = 0 , then quadratic equation has one real root.
If D > 0 , then quadratic equation has two distinct real roots.
~~~~~~~~~~~~
x² + 5x - 4
a = 1, b = 5, c = - 4
D = 5² - 4(1)(- 4) = 25 + 16 = 41