The area formula of a circle is
× π.
With that being said, we can solve both problems!
Starting with part A:
-The radius we know is 21cm. From there, we can substitute in our formula with the new value.
x π
From there, we can square our radius:
(21 x 21) x π
(441) x π
And finally, we can multiply by pi to get our answer.
(441) x π
1385.44236023
Which rounded to the nearest tenth is 1385.4. Therefore, the area of the porthole is 1385.4 centimetres.
The second part can be followed with the same process, hopefully you understand the concept enough to where you're comfortable solving problems like this on your own. Feel free to reach out if you have any further trouble!
<em>Hope this helped! :)</em>
The answer to this question is 6
Answer:

Step-by-step explanation:
we know that
The equation of a exponential growth function is given by

where
y is the value of the home
x is the number of years
a is the initial value
r is the rate of change
we have

substitute


Answer:
y ≥ 3x -1; x +3y ≤ 6
Step-by-step explanation:
Both lines are solid, so the only viable choices are those with "or equal to" in the comparison operators: the 2nd and 4th choices.
The line with a slope of +3 is shaded <u><em>above</em></u> the line, so that will correspond to the inequality ...
y ≥ 3x -1 . . . . . . . . . . found only in the 4th choice.