Question 11 (3 points) Question 11 Unsaved
The equation x2 + (y + 3)2 = 36 models the boundary on a local map for which Darren can hear his friend Tom on his two-way radio when Darren is at home. How far (in miles) can Tom walk from Darren's home and still be heard?

Question 11 options:

3 miles

6 miles

2 miles

12 miles

Question 12 (3 points) Question 12 Unsaved
The equation for the circle is:

x2+y2−12x+6y−19=0 .

What is the center of the circle?

Question 12 options:

(-6, 3)

(12, -6)

(6, -3)

(-12, 6)

Answer: For #11, he will be able to hear for 6 miles.

The equation of a circle ends with r^2 on the right sides. Right now, we have 36. We need to change this to 6^2, so we can identify the radius as 6.

For #12, you would need to put into into the equation of a circle. Then, you could identify the center.

It would be (x - 6)^2 + (y +3)^2 on the left side. Therefore, the center would be (6, -3).

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