The answer should be 1 3/8
It's closed under addition. You can take any two natural numbers you want, add them up and you'll get some other natural number (eg: 3 and 5 ---> 3+5 = 8)
it's not closed under subtraction. Sure 5-3 = 2 is a natural number but 3-5 = -2 is not a natural number
so that leads us to the answer being choice B
Answer:
|8-x|=3
Step-by-step explanation:
Find the average
11+5=16
16*1/2=8
8-5=3
8-11=-3
|3|=|-3|
|8-x|=3
Are there different choices for the answer? You did not list any equations to choose from
Answer:
Rui will reach his lowest altitude after diving for 10 seconds
Step-by-step explanation:
In the quadratic equation y = ax² + bx + c, the coordinates of the lowest or the highest point is (h, k), where
- h =
and k = y at x = h
In the given question
∵ d(x) =
x² - 10 x
∵ d represents his altitude in meters after x seconds
→ Compare it with the form above to find a and b
∴ a =
and b = -10
∵ h =
→ Substitute the values of a and b in the rule to find h
∴ h =
= 10
∴ h = 10
∵ h is the x-coordinate of the lowest point
∴ The time of the lowest altitude is 10 seconds
∴ Rui will reach his lowest altitude after diving for 10 seconds