Answer:
12 years old.
Step-by-step explanation:
1) 2x+x=18
2) Now solve 2x+x=18
Add alike terms
3x=18
Now divide both sides by 3 (3x/3 and 18/3)
x=6
So Hannah is 6 years old. Her sister must be 12.
Answer:
a/sinA = b/sinB = c/sinC
Step-by-step explanation:
Answer:

And solving for the radius we got:

And replacing the data given we got:

And this value converted to meters is 
Step-by-step explanation:
For this case we know the population size
and we also know the population density 
We can assume that the area is a circle. We also know that the formula for the population density is given by:

Where P represent the number of people and A the area. Since we are assuming a circle then the area is given by:

With X the radius of the circle
And then the populationd density become:

And solving for the radius we got:

And replacing the data given we got:

And this value converted to meters is 
Answer:
3x
Step-by-step explanation: