Answer:
Step-by-step explanation:
- Speed in one direction = 40 km/h
- Speed on return = x
- Average speed = 60 km/h
Let the distance be d
<u>Average speed </u>
- 2d/(d/40 + d/x) = 60
- d/40 + d/x = 2d/60
- 1/40 + 1/x = 1/30
- 1/x = 1/30 - 1/40
- 1/x = (4-3)/120
- 1/x = 1/120
- x = 120 km/h
Answer:
82 inches
Step-by-step explanation:
The difference between consecutive even integers is 2, thus
let the legs be n and n + 2
Using Pythagoras' identity in the right triangle
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
n² + (n + 2)² = 58² ← expand and simplify left side
n² + n² + 4n + 4 = 3364 ( subtract 3364 from both sides )
2n² + 4n - 3360 = 0 ( divide all terms by 2 )
n² + 2n - 1680 = 0 ← in standard form
(n + 42)(n - 40) = 0 ← in factored form
Equate each factor to zero and solve for n
n + 42 = 0 ⇒ n = - 42
n - 40 = 0 ⇒ n = 40
But n > 0 ⇒ n = 40
and n + 2 = 40 + 2 = 42
Thus sum of legs = 40 + 42 = 82 inches
The air plane is rising so the change in elevation is +1000 feet. The temp dropped and is -20 degrees fahrenheit.
1 degree per 50 ft
For every 1,000 feet that it climbs, the outside temperature drops 20 ... What is the rate of temperature change in degrees Fahrenheit per foot.
Answer:
18.
a) 6k + 2y
b) 2x^2 + 2x
c) 16h
19. 4.5 cm
20.
a) x > 4.5
b) x >= 32
Step-by-step explanation:
Answer: The potential energy decreases and the kinetic energy increases
Step-by-step explanation:
When a body is at rest , the Potential energy is maximum because the body is not moving and the acceleration is therefore zero but as soon as the body starts moving , it will convert the potential energy to kinetic energy , therefore the kinetic energy will therefore increase.
