Answer:
t_a = 7 s
t_w = 5 s
Step-by-step explanation:
Given:
- The average speed in air v_a = 16 m/s
- The average speed in water v_w = 3 m/s
- The total distance D = 127 m
- The total time T = 12 s
Find:
How long did the stone fall in air and how long did it fall in the water?
Solution:
- Lets time taken by stone to drop through air as t_a = t_a.
- The time taken in water would be t_w = (12 - t_a)
- The total distance covered can be calculated as:
D = v_a*t_a+ v_w*(12 - t_a)
127 = 16*t_a + 3*(12 - t_a)
Simplify and solve for t:
91 = 16*t_a - 3t_a
13*t_a = 91
t_a = 7 s
t_w = 5 s
Answer:
x 2 y -4
Step-by-step explanation:
13x = -54 -20y give it is A
-10x = 60 + 20y give it is B
A + B the sum of the left side of equation is equal to the sum of the right side of equation
13 + (-10x) = -54 -20y + 60 + 20y
3x = 60-54
3x = 6
x=2
so put the x value in A or B equation you can receive y value (B is easier)
y = -4
#4)
cross multiply
2(8x+10) = 4 * 5x
16x + 20 = 20x
4x = 20
x = 5
Answer:
The last option is correct
Step-by-step explanation:
A translation of 2 units down takes S to the point (1, -1). Then a counterclockwise rotation about the origin takes S to the point (-1, -1) where we have S' .