In order to reduce ANY fraction to lowest terms, find any common factors of the numerator and denominator, and divide them both by it. If they still have a common factor, then divide them by it again. Eventually, they won't have any common factor except ' 1 ', and then you'll know that the fraction is in lowest terms.
Do 15 and 40 have any common factors ? Let's see . . .
The factors of 15 are 1, 3, <em>5</em>, and 15 . The factors of 40 are 1, 2, 4,<em> 5</em>, 8, 10, 20, and 40 .
Ah hah ! Do you see that ' <em>5</em> ' on both lists ? That's a common factor.
So 15/40 is NOT in lowest terms.
Divide the numerator and denominator both by 5 :
15 / 40 =<em> 3 / 8</em>
3 and 8 don't have any common factor except ' 1 '. So 3/8 is the same number as 15/40, but in lowest terms.
Answer: The equation of a circle with center (h,k) and radius r is given by (x−h)2+(y−k)2=r2 . For a circle centered at the origin, this becomes the more familiar equation x2+y2=r2
