Step-by-step explanation:
so, we just enter the given data into the given formula. and then calculate. it does not get easier than that.
d = 8km/h × 2h = 16km
Serena ran 16km in these 2 hours.
A stuntman jumping off a 20-m-high building is modeled by the equation h = 20 – 5t2, where t is the time in seconds. A high-speed camera is ready to film him between 15 m and 10 m above the ground. For which interval of time should the camera film him?
Answer:

Step-by-step explanation:
Given:
A stuntman jumping off a 20-m-high building is modeled by the equation
-----------(1)
A high-speed camera is ready to making film between 15 m and 10 m above the ground
when the stuntman is 15m above the ground.
height
Put height value in equation 1





We know that the time is always positive, therefore 
when the stuntman is 10m above the ground.
height
Put height value in equation 1







Therefore ,time interval of camera film him is 
Answer:
10
Step-by-step explanation:
If we plug in any negative number as x, the result will always be greater than 4, which rules out answers A and B
lets try plugging in 4 as x to test answer C:
2(8-4)
2(4)= 8
8 is greater than 4, therefore C is wrong.
Lets try 10 as X (answer D):
2(8-10)
2(-2)
-4
We know that -4 is less than 4, therefore it makes the inequality true! :)
It’s 180-135 which equals 45 so it is 45 degrees for X
Answer:
The car dealer must sell 105 cars in May to reach his goal.
Step-by-step explanation:
Given that the car dealer sold 84 cars in April, and wants to increase his May sales by 25%, to determine the number of cars he must sell to reach his goal it is necessary to perform the following calculation:
84 + (84 x 0.25) = X
84 + 21 = X
105 = X
Therefore, the car dealer must sell 105 cars in May to reach his goal.