# Math Help - radius of a circle

1. ## radius of a circle

Which is the radius of the circle x2 + y2 — 2(x + 3y) = 26

2. $\begin{array}{l}
x^2 + y^2 - 2\left( {x + 3y} \right) = 26 \\
\left( {x^2 - 2x} \right) + \left( {y^2 - 6y} \right) = 26 \\
\left( {x - 1} \right)^2 + \left( {y - 3} \right)^2 = 36 \\
\end{array}$

Can you finish?