Question

what is the center and radius of a circle with the given equation?

Answer 1

whats the equation??

Answer 2

x^2+^2-4x+10y=7

Answer 3

What is the standard eq for a circle?

Answer 4

If you know this, it shouldn't be too bad

Answer 5

(x-h)^2+(y-k)^2=r^2

Answer 6

x^2+y^2-4x+10y=7 this implies (x^2-4x+4)+(y^2+10y+25)=7+4+25
This implies (x-2)^2 + (y+5)^2= 6^2 .@bobtheblob1416

Answer 7

so now, you need to change your given eq, into this form, do you have any ideas on what you should do first?

Answer 8

@Princer_Jones please read http://openstudy.com/code-of-conduct

Answer 9

So then (x-2)^2+(y+5)^2=6^2 is my final answer @Princer_Jones

Answer 10

i need to input my focus and vertex? @FibonacciChick666

Answer 11

well you are not given that information

Answer 12

but good thought, first think=g you want to do is group the x terms and y terms together. We will need to complete the square in order to get the equation into standard form

Answer 13

right

Answer 14

so would we get (X^2-4x)+(y^2+10y)=7

Answer 15

good, so now, we need to complete the square so one number that when you add it to itself you get -4

Answer 16

same for 10

Answer 17

??

Answer 18

sorry im a freshman and im doing algebra 2 and not 1

Answer 19

so this is all new to me

Answer 20

? uhm, well what number can you multiply by 2 and get -4?

Answer 21

-2

Answer 22

good, how about 10?

Answer 23

5

Answer 24

alright, so now, if we had \((x+2)^2\), what do you get if you expand it?

Answer 25

(x+2)(x+2)?

Answer 26

that is true, but expand it even further. Multiply those binomials

Answer 27

I'm sorry, make that a minus sign not a plus

Answer 28

wait so foil?

Answer 29

yep

Answer 30

we get x^2-4x+4

Answer 31

ok now compare that to your eq up above, what is yours missing?

Answer 32

we have to oil the (x+10y)2?

Answer 33

^2 my bad

Answer 34

just on the x terms first

Answer 35

im not sure

Answer 36

your eq has X^2-4x right

Answer 37

ya so we have to get rid of the x on the 4

Answer 38

wait wait, so compare your expansion with x^2-4x

Answer 39

what is different

Answer 40

sorry afk, class