Answer:
D
Step-by-step explanation:
because since there is no negative sign in front of the 3x we automatially know there is no reflection so that rules out answers A and B. Then, since 3 is greater than 1 we can determine that it is a stretch which would rule out answer C so the answer is D
You simply do it the same way as a positive number, just with a negative sign in front :)
The ordered pairs already plotted have x-coordinates: -3, -2, 1, and 2.
A function cannot have two ordered pairs with the same x-coordinate.
The answer cannot have -3, -2, 1, or 2 as the x-coordinate.
Answer: First choice (-1, 2)
Mean:
E[Y] = E[3X₁ + X₂]
E[Y] = 3 E[X₁] + E[X₂]
E[Y] = 3µ + µ
E[Y] = 4µ
Variance:
Var[Y] = Var[3X₁ + X₂]
Var[Y] = 3² Var[X₁] + 2 Covar[X₁, X₂] + 1² Var[X₂]
(the covariance is 0 since X₁ and X₂ are independent)
Var[Y] = 9 Var[X₁] + Var[X₂]
Var[Y] = 9σ² + σ²
Var[Y] = 10σ²
