9514 1404 393
Answer:
68.6 m/s
Step-by-step explanation:
The speed at a given time is the derivative of the height at that time.
dh/dt = -9.8t
At t=7, the speed is ...
-9.8(7) = -68.6 . . . . . meters per second (downward)
The speed is 68.6 meters per second.
_____
<em>Additional comment</em>
Height is considered to be positive in the up direction, so velocity and acceleration are also positive in the up direction. The derivative of height will be the velocity. Its negative sign in this case indicates the object is moving in the downward direction. The speed is the magnitude (absolute value) of the velocity.
Well you can check what type of angle it is! like depending on how it is slouched like a right angle is 90° for example.
Circle: x^2+y^2=121=11^2 => circle with radius 11 and centred on origin.
g(x)=-2x+12 (from given table, find slope and y-intercept)
We can see from the graphics that g(x) will be almost tangent to the circle at (0,11), and that both intersection points will be at x>=11.
To show that this is the case,
substitute g(x) into the circle
x^2+(-2x+12)^2=121
x^2+4x^2-2*2*12x+144-121=0
5x^2-48x+23=0
Solve using the quadratic formula,
x=(48 ± √ (48^2-4*5*23) )/10
=0.5058 or 9.0942
So both solutions are real and both have positive x-values.
Answer:
Henry walks 7 kilometres from school to library
Step-by-step explanation:
Given:
1 unit = 1 Kilometre
To Find:
The distance between the library and the school
Solution:
The map below shows that Henry has walked from
-2 coordinate in the x axis to coordinate 5 along the same x axis
So he has walked a total of 7 units
Since we know that 1 unit = 1 Kilometre,
7 units will be
=> 7 x 1
=> 7 Kilometres
