I would do 3+5 so then it equals 8
Answer:
1280
Step-by-step explanation:
I think it is 1280 because 20*16*8/2=1280. I am not 100% sure.
Answer:
See below
Step-by-step explanation:

Recall

Using the chain rule

such that 
we can get a general formulation for

Considering the power rule

we have

therefore,

Now, once

we have

Hence, we showed

================================================
For the integration,

considering the previous part, we will use the identity

thus

and

Considering 
and then 
we have

Therefore,


Answer:
option D. 126 cm
Step-by-step explanation:
step 1
Find the scale factor
we know that
If two figures are similar, then the ratio of its corresponding sides is proportional and this ratio is called the scale factor
In this problem
Triangles PQR and XYZ are similar by AA Similarity Theorem
so

Let
z ---> the scale factor

substitute the given values

step 2
Find the perimeter of triangle XYZ
we know that
If two figures are similar, then the ratio of its perimeters is equal to the scale factor
Let
z ----> the scale factor
p_1 ----> the perimeter of triangle XYZ
p_2 ---> the perimeter of triangle PQR
so

The perimeter of triangle PQR is

we have

substitute


therefore
The perimeter of triangle XYZ is 126 cm