A circle is a set of points in a plane equidistant from a fixed point. It has a general formula of x² + y² = r². This is if the center is at the origin. However, if the center at point h and k, the equation becomes (x-h)² + (y-k)² = r².

We write the given equation in the form (x-h)² + (y-k)² = r² by completing the square.

x² + y² + 10x – 6y + 18 = 0

(x² + 10x + 25 )+ (y² - 6y + 9) = −18 + 25 + 9 = 16
(x + 5)² + (y + 3)² = (4)²

Therefore,

center = (-5, -5)
radius = 4

7 0

4 years ago

Solve equation -15+n= -9

Veronika [31]

Answer:

-6

Step-by-step explanation:

3 0

3 years ago

Read 2 more answers

A poll found that 58% of U.S. adult Twitter users get at least some news on Twitter. The standard error for this estimate was 2.

Radda [10]

Answer: (53.49%, 62.51%)

Step-by-step explanation:

Given : A poll found that 58% of U.S. adult Twitter users get at least some news on Twitter.

i.e. p= 0.58

The standard error for this estimate was 2.3%

i.e. S.E.=0.023

Critical value for 95% confidence : $z_{\alpha/2}=1.96$

Confidence interval : $p\pm z_{\alpha/2}(S.E.)$

i.e. $0.58\pm (1.96)(0.023)$

$=0.58\pm 0.04508=(0.58-0.04508,\ 0.58+0.04508)\\\\=(0.53492,\ 0.62508)=(53.492\%,\ 62.508\%)=(53.49\%,\ 62.51\%)$

Conclusion : We are 95% confident that the true population proportion of U.S. adult Twitter users who get some news on Twitter falls in interval (53.49%, 62.51%)

5 0

4 years ago