Answer:
144 
Step-by-step explanation:
Please use " ^ " to indicate exponentiation: x^2 + 3x - 4 = 0
Here, a = 1, b = 3 and c = -4.
The formula for the discriminant is b^2 - 4(a)(c).
Substituting the given values of a, b and c, we get:
(3)^2 - 4(1)(-4)
Evaluating this, we get 9 + 16 = 25.
The discriminant is 25.
-3 plus or minus √25
Taking this further, x = ------------------------------------
2
-3 plus or minus 5
or: x = -------------------------------- => {-4, 1} (solutions)
2
Answer:
a. The empirical rule.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed(bell-shaped) random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
So the correct answer is:
a. The empirical rule.
