Answer:
20 sides
We know that if we find the size of an exterior angle for the given regular polygon whose exterior angle is 18∘, we can find the number of sides. Where, n is the number of sides. Therefore, there are 20 sides in the given regular polygon whose exterior angle is 168∘.
Step-by-step explanation:
x² + y² − 8x + 10y − 8 = 0
Rearrange:
x² − 8x + y² + 10y = 8
To complete the square, take half of the x and y coefficients, square it, then add the result to both sides.
(-8/2)² = 16
(10/2)² = 25
x² − 8x + 16 + y² + 10y + 25 = 8 + 16 + 25
x² − 8x + 16 + y² + 10y + 25 = 49
Factor the squares:
(x − 4)² + (y + 5)² = 49
The center is (4, -5) and the radius is 7.
Answer:
(9, 6)
Step-by-step explanation:
the given points are
(3, 2)
(6, 4)
so, can you see, how the sequence continues ?
I see immediately that for every 3 additional units of x we add 2 units of y.
so, yes, the next point in the sequence is
(6 + 3, 4 + 2) = (9, 6).
so, this point (or ordered pair) follows the same ratio or proportional relationship between x and y as the points already in the graph.
in other words, they are on the same line following the same slope ("y coordinate change / x coordinate change" when going from one point on the line to another).
Answer:
c) Is not a property (hence (d) is not either)
Step-by-step explanation:
Remember that the chi square distribution with k degrees of freedom has this formula

Where N₁ , N₂m ....
are independent random variables with standard normal distribution. Since it is a sum of squares, then the chi square distribution cant take negative values, thus (c) is not true as property. Therefore, (d) cant be true either.
Since the chi square is a sum of squares of a symmetrical random variable, it is skewed to the right (values with big absolute value, either positive or negative, will represent a big weight for the graph that is not compensated with values near 0). This shows that (a) is true
The more degrees of freedom the chi square has, the less skewed to the right it is, up to the point of being almost symmetrical for high values of k. In fact, the Central Limit Theorem states that a chi sqare with n degrees of freedom, with n big, will have a distribution approximate to a Normal distribution, therefore, it is not very skewed for high values of n. As a conclusion, the shape of the distribution changes when the degrees of freedom increase, because the distribution is more symmetrical the higher the degrees of freedom are. Thus, (b) is true.