8
round each number to the nearest 10, then
640 ÷ 80 = 8 ← estimate
Answer:
In a right triangle, a 2 + b 2 = c 2, where a and b are the lengths of the legs and c is the length of the hypotenuse. This is called the Pythagorean theorem.
Step-by-step explanation:
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
None
If the discriminant b² - 4ac < 0
There are no real solutions
Answer:
infinite solutions
Step-by-step explanation: