What is the radius of a circle whose equation is x2+y2−10x+6y+18=0?

The radius is 4 units

Step-by-step explanation:

We can find the radius of a circle through the following procedure:

Complete the square for x and y  

Put in the format for a circle. (x-h)² + (y-k)² = r², center at (h,k) with radius = r

x2+y2−10x+6y+18=0

Now subtract 18 from both sides.

x^2+y^2−10x+6y+18-18=0-18

x^2 - 10x + y^2 + 6y = -18

(x-5)^2 - 25 + (y+3)^2 - 9 = -18

(x-5)^2 + (y+3)^2 = -18+9+25

(x-5)^2 + (y+3)^2 = 16

So,

r^2 = 16

Take square root at both sides:

√r^2 = √16

r = 4

Thus the radius is 4 units

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!

i would say b) is your answer

sorry if im wrong

step-by-step explanation: