Remember that the equation of a circle is:

Where (h, k) is the center and r is the radius.
We need to get the equation into that form, and find k.

Complete the square. We must do this for x² - 6x and y² - 10y separately.
x² - 6x
Divide -6 by 2 to get -3.
Square -3 to get 9. Add 9,
x² - 6x + 9
Because we've added 9 on one side of the equation, we have to remember to do the same on the other side.

Now factor x² - 6x + 9 to get (x - 3)² and do the same thing with y² - 10y.
y² - 10y
Divide -10 by 2 to get -5.
Square -5 to get 25.
Add 25 on both sides.

Factor y² - 10y + 25 to get (y - 5)²

Now our equation is in the correct form. We can easily see that h is 3 and k is 5. (not negative because the original equation has -h and -k so you must multiply -1 to it)
Since (h, k) represents the center, (3, 5) is the center and 5 is the y-coordinate of the center.
Two fifths are 4 one fourth is 2 so there are 2 red guppies the fraction that they are red is 2 over 4 the fraction that are not red are 2 over 4 too
Tell me the question and I’ll help you with it is it simplify or evalute etc.
Answer:
Step-by-step explanation:
1. x+2y=6 or x=6-2y
3x-2y=2
3(6-2y)-2y=2
18-6y-2y=2
18-8y=2
-8y=-18+2
-8y=-16
y=-16/-8
y=2 ans.
x+2*2=6
x+4=6
x=6-4=2 ans.
Proof:
3*2-2*2=2
6-4=2
2=2
I leave the rest for you to practice with.
3. 4x+y=7
2x+5y=-1
5. 3x+2y=-2
6x-y=6
Solve the system using the elimination method. Show all your steps.
7. -3x+3y=3
3x+y=9 add.
---------------------------------
4y=12
y=12/4
y=3 ans.
3x+3=9
3x=9-3
3x=6
x=6/3
x=2 ans.
Proof:
-3*2+3*3=3
-6+9=3
3=3
I'll leave the rest for practice.
9. -5x+12y=20
x-2y=-6
11. 3x+2y=1
4x+ 6y= 7