Method 1: In order to find out the area of an octagon with a radius of 4 feet, we have to split the whole figure into 8 equal isosceles triangles.
Therefore,
We will find out the area of one triangle and multiply the area with 8 to, figure out the area of the whole octagon there are 8 similar triangles and all of them will have the same area.
Method 2: From method 1, it would take time as there are too much of calculation, therefore we would go for the shortcut using the formula:
Area = 2√2 × r²
where r<span> is the radius of the octagon.
Substituting the values,
We get:
</span>
Area = 2√2 × 4²
Area = 2√2 × 16
Area = 2× 1.41 × 16
Area = 2.828 × 16
Area = 45.25
Rounded to the nearest tenth:
Area = 45.3 ft²
Explanation:
First you had to square from both sides of equation form.

Then you expanded form.



Solve by equation form.

Add by four from both sides of equation form.

Simplify.

Verified solutions.

Final answer: 
Hope this helps!
And thank you for posting your question at here on brainly, and have a great day.
-Charlie
Answer:

Step-by-step explanation:
Given that the bag contains black and red marbles.
Number of black marbles in the bag = 2
Number of red marbles in the bag = 3
Total number of marbles in the bag = Number of black marbles + Number of red marbles = 2 + 3 = 5
Let us have a look at the formula for probability of an event E, which can be observed as:


Now, the marble chosen at first is replaced.
Therefore, the count remains the same.

Now, the <em>required probability</em> can be found as:

Answer:

Step-by-step explanation:

All Done!