Answer:
20. 300π m³
21. 457 1/3 π cm³
Step-by-step explanation:
20. r = 10 ÷ 2 = 5
V = 5² × 12 × π = 25 × 12π=300π m³
21. r = 14 ÷ 2 = 7
V = 457 1/3 π cm³
Answer:
480/(x+60) ≤ 7
Step-by-step explanation:
We can use the relations ...
time = distance/speed
distance = speed×time
speed = distance/time
to write the required inequality any of several ways.
Since the problem is posed in terms of time (7 hours) and an increase in speed (x), we can write the time inequality as ...
480/(60+x) ≤ 7
Multiplying this by the denominator gives us a distance inequality:
7(60+x) ≥ 480 . . . . . . at his desired speed, Neil will go no less than 480 miles in 7 hours
Or, we can write an inequality for the increase in speed directly:
480/7 -60 ≤ x . . . . . . x is at least the difference between the speed of 480 miles in 7 hours and the speed of 60 miles per hour
___
Any of the above inequalities will give the desired value of x.
X=5 , x=3 - just plug in 2 and 3 into x and the lines will make it positive instead of negative
Answer:
1) 250 meters= 0.25 km
2) 12 meters= 0.012km
3) 1 meter= 0.001 km
The constant of proportionality is 1000 meters in 1km (1000 meters)
I think there’s a mistake on the second part because 1 meter does not equal to 1000km. but I did part 1 for you!
Answer : 
(1) 
Use FOIL method to mulitply (3x – 5)(3x – 5)
(2) 
Use FOIL method to mulitply (3x - 5)(3x + 5)
(3) 
Use FOIL method to mulitply -(3x + 5)(3x + 5)
(4) 
Use FOIL method to mulitply -(3x + 5)(3x - 5)
So equation 2 is true
