What are the center and the radius of the circle 4x2 + 4y2 - 4x + 16y + 1 = 0?

Center of circle: (1, -2)

Radius: √6

Step-by-step explanation:

First, we need to isolate the constant:

Then, we can divide the whole equation by 4:

Then, we can complete the square(reminder: (a+b)^2 = a^2 + 2ab + b^2)

Now that we got the standard equation of the circle, we can find the center and radius by using the equation , where (h, k) is the coordinate of the center, and r is the radius.

Therefore, the center of the circle is (1, -2), and the radius of the circle is √6.

Step-by-step explanation:

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)

14

step-by-step explanation: