The easiest way is to try the point (-4,1), that is, x=-4, y=1,
to see which equation works.
b works.

The usual way to do it is to find the equation of the circle
standard form of a circle is (x-h)²+(y-k)²=r², (h,k) are the coordinates of the center, r is the radius.
in this case, the center is (-2,1), so (x+2)²+(y-1)²=r²
the given point (-4,1) is for you to find r: (-4+2)²+(1-1)²=r², r=2
so the equation is (x+2)²+(y-1)²=2²
expand it: x²+4x+4+y²-2y+1=4
x²+y²+4x-2y+1=0, which is answer b.

5 0

3 years ago

"Suppose that you are a city planner who obtains a sample of 20 randomly selected members of a mid-sized town in order to determ

frosja888 [35]

Answer: 2.093

Step-by-step explanation:

As per give , we have

Sample size : n= 20

Degree of freedom : df= n-1=19

Significance level : $\alpha: 1-0.95=0.05$

Since , the sample size is small (n<30) so we use t-test.

For confidence interval , we find two-tailed test value.

Using students's t-critical value table,

Critical t-value : $t_{\alpha/2, df}=t_{0.025,19}=2.093$

Thus, the critical value for the 95% confidence interval = 2.093

4 0

3 years ago

If 5x = 10, then x = 2. <br> Converse: <br> Inverse: <br> Contrapositive:

miv72 [106K]

Weed good smoke and drink

6 0

3 years ago