Answer:
The rock will take about 4.5 seconds to reach the river
Step-by-step explanation:
* lets study the situation of the rock
- The rock is dropped means the initial velocity is zero
- The motion is free fall under earth gravity
- The rock dropped from a bridge 320 feet above the river
- The equation of the pathway is h = -16t² + 320
- When the rock reach to the ground the height will be zero
* Now lets substitute h by zero in the equation to find t
∵ h = -16t² + 320
∵ h = 0
∴ 0 = -16t² + 320 ⇒ add 16t² to both sides
∴ 16t² = 320 ⇒ divide both sides by 16
∴ t² = 320/16 = 20
∴ t² = 20 ⇒ take √ for both sides
∴ t = √20 = 2√5 ≅ 4.5 seconds
* The rock will take about 4.5 seconds to reach the river
Answer:
84 degrees
Step-by-step explanation:
Applying the Cosine Rule (Choice 2 is the correct one) :-
12^2 = 11^2 + 6^2 - 2*11*6 cos Y
144 = 121 + 36 - 132 cos Y
cos Y = (121 + 36 - 144) / 132
cos Y = 0.09848
Y = 84.3 degrees
<h3>
Answer: x = 45</h3>
Work Shown:
x+x+90 = 180 .... all three angles of a triangle add to 180
2x+90 = 180
2x = 180-90
2x = 90
x = 90/2
x = 45
This is a 45-45-90 right triangle. We also consider it an isosceles right triangle because the base angles (45) are equal.
U times any number by 3 and see witch ones the closest
27x3=81 that's what I think and that's the closest
Answer:
The y intercept for the equation is (0,-7)
