Given:
Area of a sector = 
Radius = 5 cm
To find:
The central angle.
Solution:
The area of a sector is:

Where, r is the radius and
is the central angle in radians.
Putting
in the above formula, we get

Multiply both sides by 2.

Divide both sides by 25.


Therefore, the central angle in radians is
.
Answer:
400 cm squared
Step-by-step explanation:
Since a square has all equal sides, this would mean the the all the other sides are 20 as well. To get the area, you would just multiply 20 by 20 to get 400. :)
Answer:

Step-by-step explanation:
we have
-----> equation A
----> equation B
we know that
The solution of the system of equations is the point 
so
The solution of the equation
is equal to the x-coordinate of the solution of the system of equations
therefore
The solution is 
<h3><u>How to solve this problem?</u></h3>
The way I would solve this problem is by first finding the unit rate, or the rate that the jet plane travels in one minute. Then I would multiply the rate by the number of minutes I want to know how far the jet plane flies; in this case it would be multiplied by 18 minutes.
<h3><u>Finding the unit rate.</u></h3>
Let's start by finding the unit rate. To find the unit rate we would divide the ratio, 450 miles:60 minutes (one hour) by 60 minutes to make the 60 minutes become one minute and 450 miles become 7.5 miles.
450 miles:60 minutes ÷ 60/60
7.5 miles:1 minute
<h3><u>Solving the question.</u></h3>
The unit rate is 7.5 miles per minute. Since we know the jet plane flies 7.5 miles every one minute, we can multiply this amount by 18 minutes to find how many miles the place can fly in 18 minutes.
7.5 miles * 18 minutes = 135 miles
The answer to your question is the jet plane travels 135 miles in 18 minutes.