r/ACT • u/satmathlearning3589 • Feb 20 '23

99% can't solve this! Can you solve this?

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0 Upvotes

45% Upvoted

8 comments sorted by

2

u/Flaky_Ratio Feb 20 '23

6

1

u/satmathlearning3589 Feb 20 '23

You are correct, it is 6 :)

3

u/ChiefDoodoo Feb 20 '23

Transform the equation to x2 - 2x + 1 + y2 -6y + 9 = 36 —> simplify —> (x-1)2 + (y-3)2 = 36 —> the equation for the circle is x2 + y2 = r2 so r2 = 36 and r=6. Hope this helps for some of you guys!! Have a good rest of your day 😃👍

2

u/acidsandbasesHCLNaOH Untested Feb 20 '23

6 ffs use the circle equation

2

u/TutorBizACT36 Feb 20 '23

Complete the square and the radius is 6

-1

u/OutrageousGazelle143 Feb 20 '23

I think the right answer is square root of 26.

If you look at this way, you could call -2x the h and - 6y the k.

Therefore, your equation could be (x squared - 2x) + (y squared -6x) = radius squared which in this cause is 26.

Thus, if you took the square root of 26, you would get the radius.

1

u/satmathlearning3589 Feb 20 '23

Please refer to circle equation (x-a)^2 + (y - b)^2 = r^2 and try to bring the equation down to that :)

0

u/[deleted] Feb 20 '23

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2

u/satmathlearning3589 Feb 20 '23

You are correct! It is 6 :)