Rational Number are set of numbers that can be written as a/b where a and b are integers, but b is not equal to 0; an integer or a fraction; for example: 6 can be expressed as 6/1 and 0.5 can be expressed as 1/2.
Answer:
Square each number: 1 , 2 , 3 , 4 , 5:
1² = 1 * 1 = 1
2² = 2 * 2 = 4
3² = 3 * 3 = 9
4² = 4 * 4 = 16
5² = 5 * 5 = 25
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You are right. In circle equation we have =r² so the correct answer will be C od D. But we have to calculate the center of a circle.

Complete the square:

And we have:

So the answer is C (the same left side of equation).
Number 2 is $4 not $.40 and 3 is 10% OFF not added to. Those are all I had time to check but 1 is right
A ratio of 11x to 10x
Where x is a number to keep the ratio the same.
Perimeter = 84
Perimeter = 2 (Length + breadth)
84 = 2 ( 11x + 10x)
84 = 2(21x)
21x = 42
x=2
So that means the actual length of the sides would be:
11 x 2 : 10 x 2
22 : 20
So that means the length can be 22, and the breadth will be 20.
Or the length is 20, and the breadth is 22.