Answer:
It will take the boulder approximately 4.28 seconds to hit the road
Step-by-step explanation:
The given height of the cliff from which the boulder falls, h = 90 feet
The equation that can be used to find the time it takes the boulder to fall is h = u·t + (1/2)·g·t²
Where;
h = The height of the cliff = 90 ft.
u = The initial velocity of the boulder = 0 m/s (The boulder is assumed to be at rest when it falls)
g - The acceleration due to gravity ≈ 9.81 m/s²
t = How long it will take for the boulder to hit the road below
Plugging in the values gives;
90 = 0 × t + (1/2)×9.81×t² = 4.905·t²
∴ t = √(90/4.905) ≈ 4.28
The time it takes the boulder to hit the road, t ≈ 4.28 seconds.
Answer:
1) 
2) 
3) 
4) 
5) 
Step-by-step explanation:
To solve each proportion, we apply cross multiplication.
Question 1:


Simplifying both sides by 5

Question 2:


Simplifying both sides by 20

Simplifying by 3

Simplifying by 2

Question 3:


Simplifying both sides by 7

Simplifying both sides by 3

Question 4:



Question 5:


Simplifying by 2, both sides

Simplifying by 8, both sides

Answer: x=26
Step-by-step explanation:
1. Write the equation 2x-5+4x-1+30=180 because all triangle angles add up to 180°
2. Simplify the equation by combining like terms. Write the equation as 6x+24=180
3. Subtract 24 from both sides. Write the equation as 6x=156.
4. Divide 156/6 and get 26. That is your answer (x=26).
Answer:
Step-by-step explanation:
(36×100) /90 = 40%
Answer:
40 minutes
Step-by-step explanation:
Let c represent the number of minutes it would take colleen to finish the job when he is working alone. Hence, it can be represented by the equation:

Solving the quadratic equation to get c gives:
c = -12 and c = 40
Since the time cannot be negative, hence c = 40 minutes.
It would take colleen 40 minutes to clear the yard of leaves alone