Answer:
Center (4, -13)
Radius = 17
Step-by-step explanation:
Circle equation: 
(h, k) is the center of the circle and the r is the radius.
h = 4, k = -13, r = 17
Answer:63
Step-by-step explanation:
Measure of what? I'll help you in the comments if you can tell me.
Answer: <span><span>{x|x ∈ U and 2x is prime} is an empty set.
</span>Justification:
</span>
U = {x|x is a positive integer greater than 1} = {2, 3, 4, 5, 6, ...}<span>
1) {x|x ∈ U and (1/2) x is prime}
Take x = 4 => (1/2) 4 = 4 / 2 = 2 = prime, so this is not empty.
{x|x ∈ U and 2x is prime}
2) 2x = {4, 6, 8, 10, 12, } so none of them is prime, hence this is an empty set.
3) {x|x ∈ U and (1/2) x can be written as a fraction}
Take any x that is odd. For example x = 3
=> (1/2)x = (1/2)3 = 3/2 which is a fraction, so this is not an empty set.
2) {x|x ∈ U and 2x can be written as a fraction}
Take any value of x, for example x = 7 => 2 = 14, and 14 = 28 / 2 so this is not an empty set.
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