Answer:
17.6 minutes
Step-by-step explanation:




Letter A is right
Explanation: best of luck
Answer:
21
Step-by-step explanation:
Mass of freight train: 9.98 • 106
= 1057.88 kg
mass of aircraft carrier: 7.3 • 107
= 781.1 kg
difference: 1057.88 - 781.1
= 276.78 kg
= 2.7678 x 10^2
Answer: B. The coordinates of the center are (-3,4), and the length of the radius is 10 units.
Step-by-step explanation:
The equation of a circle in the center-radius form is:
(1)
Where
are the coordinates of the center and
is the radius.
Now, we are given the equation of this circle as follows:
(2)
And we have to write it in the format of equation (1). So, let's begin by applying common factor 2 in the left side of the equation:
(3)
Rearranging the equation:
(4)
(5)
Now we have to complete the square in both parenthesis, in order to have a perfect square trinomial in the form of
:
<u>For the first parenthesis:</u>

We can rewrite this as:

Hence in this case
and
:

<u>For the second parenthesis:</u>

We can rewrite this as:

Hence in this case
and
:

Then, equation (5) is rewritten as follows:
(6)
<u>Note we are adding 9 and 16 in both sides of the equation in order to keep the equality.</u>
Rearranging:
(7)
At this point we have the circle equation in the center radius form 
Hence:


