2. A circle with radius 5 is tangent to the $x$-axis, the $y$-axis, and the line $4 x-3 y+10=0$. Find its center.
Answer: $(-5,5)$
Solution: The $x$ and $y$-intercepts of the given line are $-5 / 2$ and $10 / 3$, respectively. This means that the line and the coordinate axes determine a circle on the second quadrant, and so the center is at $(-5,5)$