Answer:

Step-by-step explanation:
For each right-angled triangle:

Because 
we have an equation

multiplying both sides by x, we get 
dividing both sides by 0.4 and 
using calculator, we divide 12 by 0.4
and finally x=30
Answer:
Only one
Step-by-step explanation:
46=3x+7 /-7
39=3x /:3
13=x
Answer:
About 113,097.34 units
Step-by-step explanation:
The volume of a sphere can be found with the equation V =
πr³ when r is the radius.
V =
πr³
V =
π(30)³
V ≈ 113,097.34 units
Answer:
- 6
Step-by-step explanation:
The average rate of change of f(x) in the closed interval [ a, b ] is

Here [ a, b ] = [ - 1, 4 ] , then
f(b) = f(4) = 4³ - 6(4)² - 4 = 64 - 96 - 4 = - 36
f(a) = f(- 1) = (- 1)³ - 6(- 1)² - (- 1) = - 1 - 6 + 1 = - 6 , then
average rate of change =
=
=
= - 6
Answer: u=7
Step-by-step explanation:
-6= -2u+4(u-5)
-6= -2u+4u-20
-6= 2u-20
14= 2u
7=u