### Home > CCA2 > Chapter 8 > Lesson 8.1.2 > Problem8-42

8-42.

A circle with its center on the line $y = 3x$ in the $1$st quadrant is tangent to the $y$-axis. .

1. If the radius is $2$, what is the equation of the circle?

What point on the line $y = 3x$ is $2$ units from the $y$-axis?

Use the coordinates of the center and the radius to write an equation in general form.

2. If the radius is $3$, what is the equation of the circle?

See part (a).

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