I do belive the first one is 30
Answer:
C. (0, -3)
Step-by-step explanation:
The given system is


The point that satisfies both inequalities is the solution to the system.
When x=0 and y=-3.
We substitute into the first inequality to get:

We again substitute into the second inequality to get:

The point (0,-3) is a solution to the system of inequalities.
Answer:
C. heteroscedasticity
Step-by-step explanation:
The OLS regression assumption of error variance being constant irrespective of independent variables, is called Homoscedasticity.
Var (u | x) = σ^2 (u) ;
where u = error term, x = independent variable, σ^2 (u) = constant error variance
The violance of this assumption ie Var (u | x) is related to independent variable x, is called Heteroscedasticity.
Answer:the number of BlackBerry that Arlene had initially was 276
Step-by-step explanation:
Let x represent the number of BlackBerry that Arlene had initially.
She gave 216 to her teachers. This means that she is left with x - 216
Then she dropped 12. This means that she would be left with x - 216 - 12 = x - 228
Later, she ate 18. This means that she would be left with x - 228 - 18 = x - 246
Finally, she gave half of what she had to her friend. This means that the amount that she gave to her friend is (x - 246)/2 and the amount that she has left would be
(x - 246)/2
Now, she has 15. This means that
(x - 246)/2 = 15
x - 246 = 2 × 15 = 30
x = 30 + 246 = 276