# Replace the given Cartesian equation with an equivalent polar equation. {eq}x^2 + y^2 - 4x = 0 {/eq}

## Question:

Replace the given Cartesian equation with an equivalent polar equation.

{eq}x^2 + y^2 - 4x = 0 {/eq}

## Converting Cartesian Equation to Polar Equation:

To convert a cartesian equation to polar equation, we will use the following rules:

{eq}x = r \cos (\theta ) \, \text{and} \, y = r \sin (\theta ), {/eq}

and {eq}r^2 = x^2 + y^2. {/eq}

Where, {eq}(x,y) {/eq} is a point in cartesian coordinates and {eq}(r, \theta ) {/eq} is a point in polar coordinates.

In polar coordinates, {eq}r {/eq} determines the distance from origin to the point and {eq}\theta {/eq} determines the angle between the line which is from origin to the point and the {eq}x- {/eq}axis.