Okay, first, given the equation, we need to find out what the radius of the circle is. Let us state the general equation of a circle:

Where

is the centre of the circle. In this case, we don't need to know the centre. Just the radius.
Let us start by converting the equation into standard for, which I typed above. Divide both sides by 81.

Great! We now know the radius of the circle. It is

because it is the bottom fraction. Now we know that the radius is 9.
So now lets input this into the area of circle formula:
Now we insert our radius.
You can convert that into a decimal if you wish.
Hope this helped!
~Cam943, Moderator
Answer: 756
Step-by-step explanation:
The president can be elected in 28 different ways. After a student is elected president, there are 27 students left to elect a vice president from. So there are 28 x 27 = 756 different arrangements.
Answer: 13
Step-by-step explanation:
1. Harry has 20/20 sweets
2. Nadia takes 7/20 sweets
3. Your left with 13/20
Answer:
D. Subtract 4 from both sides
Explanation:
I just learned about quadratic equations in school. The first step of solving quadratic equations is to make sure it is in standard form and equal to 0.
Standard form:
ax^2 + bx + c = 0