Question

Write the equation of the circle in standard form.  Find the center, radius, intercepts, and graph the
circle.
x^2 + y^2 + 10x +8y + 16 = 0

Answer 1

1. Move the 16 to the right side of the equation.
2. Group terms with similar variable.
3. Then find the perfect square of each variable (b/2)^2, for x-terms that would be
(10/2)^2=25, for the y-term it would be (8/2)^2 = 16.
4. Add 16 and 25 to both sides.
5. Find the perfect squares for each variable (e.g x^2+10y+25 = (x+5)^2).
What is y^2+8y+16 as a perfect square?
6. Then you should get the answer.

Answer 2

Are you working on the question using the steps above? at what point are you lost?

Answer 3

I don't understand the way how your explaining it.

Answer 4

you lost me at step 3

Answer 5

Step 1:
x^2+10x+y^2+8y+16=0
Step2:
x^2+10x+y^2+8y=-16 (move the 16 to the right hand side by subtraction)

Step3:
For the x-term 'b' =10
For the y-term 'b' = 8
So to find the number that would make the x-term and y-term perfect squares we use (b/2)^2
So we get: x^2+10x+(10/2)^2+y^2+8y+(8/2)^2 = -16+(10/2)^2+(8/2)^2
(x^2+10x+25)+(y^2+8y+16) = -16+16+25
(x^2+10x+25)+(y^2+8y+16) = 25

Do you understand what I did here?

Answer 6

From here you just need to find the perfect squares for both terms in the parentheses and that should be your answer.

Answer 7

yes I do now thanks

Answer 8

Sure no problem