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ZnappyDooZ
 one year ago
Geometry Help Please!
ZnappyDooZ
 one year ago
Geometry Help Please!

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Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1hm, not quite, do you know how to complete the square?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1ok, just look at the x part (x^2 + 2x) if you add 1, you get x^2 + 2x + 1 which equals (x+1)^2 do you understand where the 1 comes from?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1I mean, do you understand why I added 1?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1Nope, I didn't do anything to the 2x I only added 1 so I could rewrite (x^2 + 2x) in the form (x+1)^2

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1(x^2 + 2x + 1) = (x+1)^2

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1(a+b)^2 = (a^2 + 2ab + b^2), have you seen this formula before?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1Well, it's kinda hard to explain, but you want to rewrite (x^2 + 2x) in the form (a+b)^2 or (ab)^2 by adding a number

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1can you try rewriting (y^2 + 4y + ___) in the form (y+b)^2? can you try filling in the blank so you get an expression in the form (y+b)^2

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1in other words, what value should we add to make the expression equal to (y+b)^2 where b is a constant? i'm sorry, this is hard to explain D:

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1ok, I'll give you a hint: we can add a number to y^2 + 4y to get (y+2)^2 what is that number?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1hint: try expanding (y+2)^2 = (y+2)(y+2)

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1yup! and how do we get from y^2 + 4y to y^2 + 4y + 4?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1this might be helpful in explaining the concept, http://www.purplemath.com/modules/sqrcircle.htm

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1nope, you add 4 to the expression

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1alright, I think I might have a better way to explain this...

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1ok, after all the math we just did, we have: (x+1)^2 + (y+2)^2 = 20 + 4 + 1 remember, we added 4 and 1 to the left side, so we must add 4 and 1 to the right side

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1(x+1)^2 + (y+2)^2 = 25, are you with me so far?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1alright, you know that the general equation of a circle is (xh)^2 + (yk)^2 = r^2, where r is the radius and (h,k) is the center, right?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1can you tell me what h, k, and r are, based on what we just found out?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1not quite, check your math again check the signs on h and k, and check r r^2 = 25, so what is r?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1right, and what are h and k?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1not quite! h = 1 k = 2 so, what are h and k?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1yup! make sure to check the signs! so, can you now tell me what the center and radius are?

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1that's it, look at the question again: "find the center and the radius of the circle", so you're done

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1actually I need to go pretty soon, can I just outline my steps for you? x^2 + 2x + y^2 + 4y = 20 (x^2+2x) + (y^2 + 4y) = 20 (x^2 + 2x + 1) + (y^2 +4y + 4) = 20 + 4 + 1 = 25 (x+1)^2 + (y+2)^2 = 25 h = 1 k = 2 r = 5

Vocaloid
 one year ago
Best ResponseYou've already chosen the best response.1ok fantastic! you did perfectly, great job ~
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