Find the value of x.

x = 57

Step-by-step explanation:

So we know all triangles add up to 180 degrees. And that supplementary angles add up to 180 degrees.

So, we can do that missing angle + 138 = 180

180 - 138 = 42

180 - 42 - 81 = x = 57

80π/3 or about 83.775

step-by-step explanation:

since a cone is 1/3 of a cylinder, we need to find the base's area. since area = πr^2, we get 16π. then, multiplying this by 5, we get 80π. dividing by 3, since the cone's volume is 1/3 of that of a cylinder's, we get 80π/3.

hope this !

4 and 5)16.97 or 12√2

6)15.59 or 9√3

7)y = 15.59 or 9√3     x =27

8)17.80