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anonymous
 one year ago
A circle has an area of approximately 78.5 square units. If the center of the circle is at (2,4). Which of the following points is on the circle?
anonymous
 one year ago
A circle has an area of approximately 78.5 square units. If the center of the circle is at (2,4). Which of the following points is on the circle?

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0(6, 4) (2, 1) (4, 4) (2, 9)

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1do you know the standard form equation of the circle ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Do you mean the distance?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1yes same equation for both

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yyeah, I can't understand how to calculate that, I do know the d formula tho ;v;

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1well the standard form equation of the circle is \[\huge\rm (xh)^2 +(yk)=r^2\] where (h,k) is the center and r = radius

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1use the formula area of a circle \[\huge\rm A= \pi r^2\] to find r (radius )

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0is (yk) also supposed to be ^2? So is h=2 and k=4??

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1yes right forgot sorry about that \[\huge\rm (xh)^2 +(yk)^2=r^2\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0And I should just try each of the options until one of them is 78.5...?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1thanks for tag i was afk alright first you need to find the radius

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1the given is 78.5 area so substitute a for 78.5 and then solve for r

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1use the formula area of a circle \[\huge\rm A= \pi r^2\] to find radius

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oohhhh 78.5=pir^2 Umm, I assume I divide pi from both sides then?

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1yes r^2 equal 25 yes right forgot sorry about that \[\huge\rm (x2)^2 +(y4)^2=25\] now you can substitute (x,y) for each order pair if you get equal sides then that order pair would be the answer

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1no we need r^2 which is 25 you can check your work 3.14*25^2 iif its equal 78.5 then 25 is correct

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0It isn't equal to 78.5 ..

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1r^2 =25 not r= so dont' take square of 25

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.1\[\huge\rm \frac{ 78.5 }{ 5 }=r^2 ~~~~> 25=r^2\] to find r you should take square root but we need r^2 for the equation

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Ooh Okay, then yeah it's rightso then I just try each of the answers in the slots for x and y until I get the right one?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh okay! I already know the correct answer which is (2,1) and I tested it and it's right! Thanks so much!! :)
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