50-x^2=0
Move the x^2 to the other side
x^2=50
Now take the square root of both sides
x=+_(50)^1/2 (^1/2 means square root)(+_ is plus or minus. Sorry XD)
Now simplify the square root
X=+_5(2)^1/2
Voila. The answer is C
Answer:

Step-by-step explanation:
The area of a regular polygon is calculated using the formula;

where
is the apothem and p is the perimeter.
It was given that, the apothem is,
and the perimeter is 
We substitute into the formula to obtain;


To the nearest square inch, we have;

Answer:
The graph in the attached figure
Step-by-step explanation:
we have

The solution of the inequality is the shaded area above the solid line of the equation of the parabola 
The vertex of the parabola is the point (0,-1)
The parabola open downward (vertex is a maximum)
using a graphing tool
see the attached figure
Answer:
The student who weighted the rock 5 times has a 95% confidence interval of (25.2, 29.1) which is guaranteed to be more wider (less precise) than the other student who weighted the rock 20 times.
Step-by-step explanation:
What is Confidence Interval?
The confidence interval represents an interval that we can guarantee that the target variable will be within this interval for a given confidence level.
The confidence interval is given by

Where
is the mean weight
is the standard deviation
is the critical value from t-table and n is the sample size.
The term
is known as margin of error.
As the sample size is decreased the corresponding margin of error increases which results in wider confidence interval which means smaller precision.
The student who weighted the rock 5 times has a 95% confidence interval of (25.2, 29.1) which is guaranteed to be more wider (less precise) than the other student who weighted the rock 20 times.
We can say with 95% confidence that the true mean weight of the rock is within the interval of (25.2, 29.1).