SOLUTION: Hi a circle is drawn on a number plane with the centre at (3,2) the circumference passes thru (3,-2) What is the area of the circle. now I used the distance formula and foun

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Question 1054961: Hi
a circle is drawn on a number plane with the centre at (3,2) the circumference passes thru (3,-2)
What is the area of the circle.
now I used the distance formula and found the radius to be the square root of -16!
The textbook solution says the radius is 4 units.
where did I go wrong?
Thanks

Found 3 solutions by ikleyn, josgarithmetic, MathTherapy:
Answer by ikleyn(53765) About Me  (Show Source):
You can put this solution on YOUR website!
.
You made a mistake in your distance formula.

Now find this mistake.

Then fix it.


Answer by josgarithmetic(39800) About Me  (Show Source):
You can put this solution on YOUR website!
RADIUS:

Distance from (3,2) to (3,-2).
You can do this one in your head and without the Distance Formula. Literally SEEING that radius is 4 units should be immediate. You stepped wrong in maybe how you applied the distance formula.


radius, sqrt%28%283-3%29%5E2%2B%282-%28-2%29%29%5E2%29---------------compute this!

Answer by MathTherapy(10810) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
a circle is drawn on a number plane with the centre at (3,2) the circumference passes thru (3,-2)
What is the area of the circle.
now I used the distance formula and found the radius to be the square root of -16!
The textbook solution says the radius is 4 units.
where did I go wrong?
Thanks
where did I go wrong? 
When you computed the distance, you got: 16+=+r%5E2
Looking at the equation, 16 IS NOT = r, but r%5E2 instead. Therefore, you have to take the square root of 16 to find r. This is 4. Understand?