Answer:
A
Step-by-step explanation:
Recall that for a quadratic equation of the form:
The number of solutions it has can be determined using its discriminant:
Where:
- If the discriminant is positive, we have two real solutions.
- If the discriminant is negative, we have no real solutions.
- And if the discriminant is zero, we have exactly one solution.
We have the equation:
Thus, <em>a</em> = 2, <em>b</em> = 5, and <em>c</em> = -<em>k</em>.
In order for the equation to have exactly one distinct solution, the discriminant must equal zero. Hence:
Substitute:
Solve for <em>k</em>. Simplify:
Solve:
Thus, our answer is indeed A.
Answer:what are that statements
Step-by-step explanation:
Answer:
a. Grand Mean = 2.799
b. Standard Deviation = 0.01387
c. Standard Error = 0.0016
d. The range with a Z score of 3 = (2.75739, 2.84061)
Step-by-step explanation:
a. Grand mean :
Given that
Sum of 80 values = 223.91
Total observation = 80
Grand mean = 223.91/80 = 2.799
b. With the excel command "STDEV[range of cells]", we get the standard deviation as = 0.01387
c. Standard error = Standard deviation / root of n
d. The range with a Z score of 3 :
lower limit = mean - (3 * SD) = 2.799 - (0.04161) = 2.75739
upper limit = mean + (3 * SD) = 2.799 + (0.04161) = 2.84061
Answer:A -3,6
Step-by-step explanation: Substitue the answers in and they work out