Answer: It will take 4 seconds for the rock to hit the water.
Step-by-step explanation:
Given : Benjamin threw a rock straight up from a cliff that was 48 ft above the water.
If the height of the rock h, in feet, after t seconds is given by the equation
To find : Time taken for the rock to hit the water.
When rock hit the water height becomes zero , i.e. put h = 0 , we get
Divide equation by 2 , we get
The Laue of x for ax²+bx+c =0 is 
So , 
Since t cannot be negative , so t= 4
Hence, it will take 4 seconds for the rock to hit the water.
Step-by-step explanation:
Reason Is because 10^-2 is
1
-----
10^2
= 1/100
=0.01
Answer:
Step-by-step explanation:
Remark
You are going to use the Pythagorean Theorem. The trick is to find the length of the leg making up the base of the triangle.
That base is equal to the difference between the two bases.
Solution
The base of the triangle = 2x + 1 - (x + 3) Remove the brackets.
base = 2x + 1 - x - 3
base = x - 2
Now the height of the trapezoid is also the second leg of the triangle. Apply the Pythagorean Theorem.
c^2 = a^2 + b^2
a = x - 2
b = x + 4
c = 2x
4x^2 = (x - 2)^2 + (x + 4)^2 Expand the brackets
4x^2 = x^2 - 4x + 4 + x^2 + 8x + 16 Collect like terms
4x^2 = 2x^2 + 4x + 20 Subtract the right side from the left.
4x^2 - 2x^2 - 4x - 20 = 0
2x^2 - 4x - 20 = 0 Divide by 2
2x^2/2 - 4x/2 - 20/2 = 0
x^2 - 2x - 10 = 0
x = - b +/- sqrt(b^2 - 4*a*c)/ 2a
a = 1
b = - 2
c = - 10
x = (- -2 + / - sqrt((-2)^2 - 4*(1)*(-10) ) / 2
x = (2 + / - sqrt(4 + 40 ))/2 Only the plus root has any meaning.
x = ( 2 + sqrt(44 ) )/2
x = ( 2 + 2*sqrt(11) ) / 2
x = 1 + sqrt(11)
sqrt(11) = 3.3166
x = 1 + 3.3166
x = 4.3166
4
Step-by-step explanation:
There are 400 students, and 100 buses, so number of student in each bus= 400/100
= 4
