Answer:
Step-by-step explanation:
20x - 44z = 84
528x + 44z = 1012
548x = 1096
x= 2
48(2) + 4z = 92
96 + 4z = 92
4z = -4
z = -1
(2, -1)
Answer:
Routine: started doing his homework.
Surprising: leaped up and started singing in Portugese with one leg in the air.
Step-by-step explanation:
Answer:
a) V_avg = 32 ft/s
b) V_avg = -30 ft/s
c) See explanation
Step-by-step explanation:
Given:
- The displacement function is given:
S(t) = -16t^2 + 64t + 80
Find:
a. Find the balls average velocity between the time it was thrown and 2 seconds later
b. Find the ball’s average velocity between 2 and 4 seconds after it was thrown
c. What do the signs in your answers to parts (a) and (b) mean in terms of the direction of the ball’s motion?
Solution:
- The average velocity of an object is the displacement over time, and it is expressed as follows:
V_avg = ( S_2 - S_1 ) / dt
- Evaluate S(2), S(0), and S(4):
S(2) = -16*2^2 +64*2 +80
S(2) = 144 ft
S(0) = -16*0^2 +64*0 +80
S(0) = 80 ft
S(4) = -16*4^2 +64*4 +80
S(4) = 80 ft
- For part a. Compute V_avg:
V_avg = ( S(2) - S(0) ) / 2
V_avg = (144 - 80) / 2
V_avg = 32 ft/s
- For part b. Compute V_avg:
V_avg = ( S(4) - S(2) ) / 2
V_avg = (80 - 140) / 2
V_avg = -30 ft/s
- We see that the signs of the Velocity have changed. The coordinate axis up against gravity was chosen to positive. While a negative access is in favor of the gravity. Hence, from the signs we can see that the ball is going down towards ground in motion from t = 2 s to t = 4 s.
0Answer:
A
Step-by-step explanation:
Find the zeros by letting y = 0 , that is
x² - x - 6 = 0 ← in standard form
(x - 3)(x + 2) = 0 ← in factored form
Equate each factor to zero and solve for x
x - 3 = 0 ⇒ x = 3
x + 2 = 0 ⇒ x = - 2
Since the coefficient of the x² term (a) > 0
Then the graph opens upwards and will be positive to the left of x = - 2 and to the right of x = 3 , that is in the intervals
(-∞, - 2) and (3, ∞ ) → option A
The answer is B 13.5 miles
