Why did I get these wrong? I'm pretty sure they're both correct...

Question

anonymous · Answer

attachment

zzr0ck3r · Answer

equation of a circle$$(x-a)^2+(y-b)^2=r^2$$

zzr0ck3r · Answer

you have =4 
which =2^2
so r = 2

anonymous · Answer

But the radius was 4... so it had to be 16. @zzr0ck3r

zzr0ck3r · Answer

equation is set = 4
this is not the radius
this is the square of the radius
so the radius is the square root of 4
this is 2

anonymous · Answer

It says the radius is 2 but in the diagram the radius is 4.

zzr0ck3r · Answer

but we are trying to say what is wrong with the diagram, given the equation

zzr0ck3r · Answer

and given the equation, the diagram is wrong because it should have a radius of 2

anonymous · Answer

Ohhhh I've got it now.

ivettef365 · Answer

what is wrong that the radius is 2 and not 4

anonymous · Answer

What about the second one?

zzr0ck3r · Answer

I think you were doing it backwards:)

ivettef365 · Answer

the second one you need to divide 4$\sqrt{2}$ /2  and then square what you get

anonymous · Answer

I feel like a doof, now XD Thanks you two.