1 3/10·b=39
(1·10+3)·b/10=39
13b/10=39
13b=39·10
13b=390|:13
<u>b=30</u>
<em>Answer: 30</em>
A tetrahedron is a shape made out of four triangular faces, and it has a total of <span>six edges
</span>
The two parabolas intersect for

and so the base of each solid is the set

The side length of each cross section that coincides with B is equal to the vertical distance between the two parabolas,
. But since -2 ≤ x ≤ 2, this reduces to
.
a. Square cross sections will contribute a volume of

where ∆x is the thickness of the section. Then the volume would be

where we take advantage of symmetry in the first line.
b. For a semicircle, the side length we found earlier corresponds to diameter. Each semicircular cross section will contribute a volume of

We end up with the same integral as before except for the leading constant:

Using the result of part (a), the volume is

c. An equilateral triangle with side length s has area √3/4 s², hence the volume of a given section is

and using the result of part (a) again, the volume is

Solve for x by plugging in y, then plug x back in
Answer:
8,791- 2,899= 5892
Step-by-step explanation:
Melinda ran 5,892 more meters on monday than tuesday