Answer:

Step-by-step explanation:
difference of a number and 9 means to subtract

twice that means multiply by 2

at least is greater than or equal to

Answer:
the greatest common factor of this is 3
Answer:
you type in the answer if you know it
Step-by-step explanation:
This is how I would solve it, I would act as if there were 36 people in the class.
36÷6=6×5=30
30÷3=10×2=20
20/36=10/18=5/9
You could also try another number such as 24;
24×(5÷6)=20
20×(2/3)=13.3(3 repeating)
13.333/24=5/9
5/9 people have dogs.
Tell me if this helps.
Answer:
a=21.1
Step-by-step explanation:
You can use the given (incorrect) equation and fill in the value of t to find h:
h = 12.5 +9sin(750(3.5)) = 3.68 . . . . feet
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Or, you can use the correct equation, or just your knowledge of revolutions:
h = 12.5 +9sin(750(2π·3.5)) = 12.5 . . . . feet
in 3.5 minutes at 750 revolutions per minute, the propeller makes 2625 full revolutions, so is back where it started — at 12.5 feet above the ground.