Answer:
x=-4 and y=3
Step-by-step explanation:
-3x-3(-5x-17)=3
-3x+15x+51=3
12x=-48
x=-4
y=-5x-17
y=20-17
y=3
Answer:
6xand 4x
Step-by-step explanation:
but mainly when a number is on bracket u have to multiply it so 8 times 6x and 6 times 4x is the numbers with like terms
Answer: x=−3 or x=−5
Step-by-step explanation:
Step 1: Factor left side of equation.
(x+3)(x+5)=0
Step 2: Set factors equal to 0.
x+3=0 or x+5=0
x=−3 or x=−5
Answer:
a) 
b)
c)
Step-by-step explanation:
Assuming the following question: Because of staffing decisions, managers of the Gibson-Marimont Hotel are interested in the variability in the number of rooms occupied per day during a particular season of the year. A sample of 20 days of operation shows a sample mean of 290 rooms occupied per day and a sample standard deviation of 30 rooms
Part a
For this case the best point of estimate for the population variance would be:

Part b
The confidence interval for the population variance is given by the following formula:
The degrees of freedom are given by:
Since the Confidence is 0.90 or 90%, the significance
and
, the critical values for this case are:
And replacing into the formula for the interval we got:
Part c
Now we just take square root on both sides of the interval and we got: