Answer:
d. 11.6
Step-by-step explanation:
The results of the first die and the second one are independent to each other. The expected value of Z is obtained, therefore, by summing the expected values of both X and Y, because Z = X+Y and X and Y are independent. As a result 
Answer:
-5≤x <1
Step-by-step explanation:
sqrt( x+5) / sqrt(1-x)
The numerator must be greater than zero since it is a square root
sqrt(x+5) ≥0
Square each side
x+5≥0
x≥-5
The denominator must be greater than zero (the denominator cannot be zero)
sqrt(1-x)> 0
Square each side
1-x > 0
1>x
Putting these together
-5≤x <1
Yes, in simplest form, both fractions are 1/3 (one over three)
Answer:
r=0
Step-by-step explanation:
7r-5r+8=9r+8-r
This is already an equation
Combine like terms
2r+8 = 8r+8
Subtract 2r from each side
2r-2r +8 = 8r-2r +8
8 =6r+8
Subtract 8 from each side
8-8 = 6r+8-8
0 = 6r
Divide by 6
0/6 = 6r/6
0 =r