Step-by-step explanation:
ED is greater than BC
the line from B to ED ^ (which i drew ) the point it touches ED name it X. so EX will be 2 ( ED-BC)(6-4).
then u have a triangle. EX, XB and EB.
you have length of EX(2) and u have hypotenuse. so u can calculate XB using Pythagoras theorem.
15.1²=2²+XB²
15.1²-2²=XB²
224.01=XB²
XB=14.97
since XB and DC are parallel ( a rectangle is forming XBCD) so DC is also 14.97
Let x represent the height of the model.
We have been given that a construction company built a scale model of a building. The model was built using a scale of 3 inches = 32 feet. We are asked to find the height of the model, if the building is expected to be 200 feet tall.
We will use proportions to solve our given problem as:
Upon substituting our given values, we will get:
Therefore, the model will be 18.75 inches tall.
Answer:
The correct answer B) The volumes are equal.
Step-by-step explanation:
The area of a disk of revolution at any x about the x- axis is πy² where y=2x. If we integrate this area on the given range of values of x from x=0 to x=1 , we will get the volume of revolution about the x-axis, which here equals,
which when evaluated gives 4pi/3.
Now we have to calculate the volume of revolution about the y-axis. For that we have to first see by drawing the diagram that the area of the CD like disk centered about the y-axis for any y, as we rotate the triangular area given in the question would be pi - pi*x². if we integrate this area over the range of value of y that is from y=0 to y=2 , we will obtain the volume of revolution about the y-axis, which is given by,
If we just evaluate the integral as usual we will get 4pi/3 again(In the second step i have just replaced x with y/2 as given by the equation of the line), which is the same answer we got for the volume of revolution about the x-axis. Which means that the answer B) is correct.