Answer:
10x+23 (pretty sure) and the * means multiply
Step-by-step explanation:

For the first question you need to find the formula for the rectangle, after you did that fill it in. and find your answer.
Answer: (2x+5)(2x−5)
Step-by-step explanation:For me, what i like to do is to try divide the problem into two parts. For example in this problem, you would divide the 4x^2 into two 4x(since 4x+4x = 4x^2). Then 25 can be divide into into 5s (5x5=25). SInce you know that its a negative 25, you know that it has to be a negative on one of the sides. So the answer in factor form is (2x+5)(2x−5)
Not sure i remember this but i think radius is like half of the diameter. it’s a line from the center, to a side of the circle. in this situation, line RO would be representing the radius.
answer: D, line RO
hope this helps :)