Given that Santiago buys milk and onions at the store and he pays a total of $25.78, and he pays a total of $3.58 for the milk and he buys 6 bags of onions that each cost the same amount, to determine an equation which can be used To determine how much each bag of onions costs, the following calculation must be made:
![\bf \textit{equation of a circle}\\\\ (x-{{ h}})^2+(y-{{ k}})^2={{ r}}^2 ~~ \begin{array}{lllll} center~(&\quad {{ h}},&\quad {{ k}}\quad )\qquad radius=&{{ r}}\\ &-\sqrt{5}&-\sqrt{5}&\sqrt{5} \end{array} \\\\\\\ [x-(-\sqrt{5})]^2+[y-(-\sqrt{5})]^2=(\sqrt{5})^2 \\\\\\ (x+\sqrt{5})^2+(y+\sqrt{5})^2=5](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Bequation%20of%20a%20circle%7D%5C%5C%5C%5C%20%0A%28x-%7B%7B%20h%7D%7D%29%5E2%2B%28y-%7B%7B%20k%7D%7D%29%5E2%3D%7B%7B%20r%7D%7D%5E2%0A~~%20%0A%5Cbegin%7Barray%7D%7Blllll%7D%0Acenter~%28%26%5Cquad%20%7B%7B%20h%7D%7D%2C%26%5Cquad%20%7B%7B%20k%7D%7D%5Cquad%20%29%5Cqquad%20%0Aradius%3D%26%7B%7B%20r%7D%7D%5C%5C%0A%26-%5Csqrt%7B5%7D%26-%5Csqrt%7B5%7D%26%5Csqrt%7B5%7D%0A%5Cend%7Barray%7D%0A%5C%5C%5C%5C%5C%5C%5C%0A%5Bx-%28-%5Csqrt%7B5%7D%29%5D%5E2%2B%5By-%28-%5Csqrt%7B5%7D%29%5D%5E2%3D%28%5Csqrt%7B5%7D%29%5E2%0A%5C%5C%5C%5C%5C%5C%0A%28x%2B%5Csqrt%7B5%7D%29%5E2%2B%28y%2B%5Csqrt%7B5%7D%29%5E2%3D5)
