The time taken by the rock will be 8.77 seconds.
<h3>What is speed?</h3>
Speed is defined as the ratio of the time distance traveled by the body to the time taken by the body to cover the distance.
Given that:-
The equation for free fall at the surface of some planet (s in meters, t in seconds) is s = 2.86t²
The time will be calculated by using the speed formula.
Speed = Distance \ Time
25.1 = 2.86t² \ t
t = 25.1 / 2.86
t = 8.77 seconds
Therefore the time taken by the rock will be 8.77 seconds.
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Answer: x= 1 , y = 7
Step-by-step explanation:
y = -6x + 13 ................. equation 1
y = 3x + 4 ................ equation 2
substitute y = 3x + 4 into equation 1 , then we have
3x + 4 = - 6x + 13
collect the like terms , we have
3x + 6x = 13 - 4
9x = 9
x = 1
substitute x = 1 into equation 2 , we have
y = 3(1) + 4
y = 3 + 4
y = 7
Therefore : x = 1 and y = 7
Answer:
You're right its B or 35
Step-by-step explanation:
Just divide 140 by 4 u get 35
2000+1200=3200=thirty two hundreds