If you are looking for the value of X i believe it is 21.6
Subtract .10 from both sides to get
.25X=5.40
Then divide both sides by .25
C(1;2)
a = 1
b = 2
r = 4
(x-a)² + (y-b)² = r²
(x-1)² + (y-2)² = 4²
(x-1)² + (y-2)² = 16
Answer: Option D.
Step-by-step explanation:
You can calculate the surface area of this right prism by adding the area of its faces.
You can observe that the faces of the right prism are: Three different rectangles and two equal triangles.
The formula for calculate the area of a rectangle is:

Where "l" is the lenght and "w" is the width.
The formula for calculate the area of a triangle is:

Where "b" is the base and "h" is the height.
You can observe that the hypotenuse of the each triangle is the width of one of the larger rectangle, then , you can find its value with the Pythagorean Theorem:

Where "a" is the hypotenuse and "b" and "c" are the legs of the triangle.
Then, this is:

Therefore, you can add the areas of the faces to find the surface area of the right prism (Since the triangles are equal, you can multiply the area of one of them by 2). This is:

Approximately 9 meters are in 10 yards, (as there is approximately 1 meter in a yard, .9144 to be exact.)
Since the problem is not telling us the height of Silvio, we are going to assume it is not relevant for our calculations.
Let

the altitude of the incoming plane. We know for our problem that the distance between Silvio and the tower is 3 miles, Also we know that the angle of elevation to the plane is 40°. With this information we can create a triangle as shown in the figure. We need a function that relates the angle of elevation with its opposite and adjacent sides, that function is tangent.




We can conclude that we should use the trig function tangent to model this situation; also, we can conclude that the equation that describes this situation is

.