A radius is a straight line from the centre to the edge of a circle. i’m not sure about any examples sorry :/
Answer: The answer is A.
Step-by-step explanation:
Sabrina should be careful of those ants and bees.
Example: 
We can see that there is more than one number with the variable x, therefore, we say they're ''like terms'' and because of that they can be summed. We do this with all of the other numbers with similar variables. If no numbers with similar variables are left, like 4a, you don't do anything but write them as they are. You can also see that 8 and 9 can also be summed because neither of them has a variable, therefore they're similar.
In this step, you just do the operation with the numbers and keep the same variable.


since there are not more numbers similar in variables, this operation is done.

It would be 2(x+3)(x+1)=0
Explanation:
I used factor by grouping. You multiply the first term (2) by the last term (6). This gives you 12 then take the factors of 12 that add up to the middle term 8. You get 6 and 2.
It should look like 2x^2+6x+2x+6=0
when you do factor by grouping you factor the first two terms and then the last two terms separately. So you get (2x+2) and (x+3). (2x+2) could be factored into 2(x+1). Then you put everything together and get 2(x+3)(x+1)=0