(a)

The point is in third quadrant.

Required points having -coordinate as and distance from is .

Plot the circle center at and radius of the circle is .

Since -coordinate is , plot the point .

Connect the plotted points.

Find the coordinates above and below of  lies on the circle.

Pythagorean theorem:

Case 1:

.

Case 2:

.

, .

The points have -coordinate of  , whose distance from are , .

Graph:

The points have -coordinate of whose distance from are , .

(b)

The point is in third quadrant.

Required points having - coordinate is and distance from is .

Calculate the distance between two points by using formula,

.

, and .

Substitute for , for , for and for in above formula.

Square on both sides.

Apply zero product property.

  and 

  and  .

The points have -coordinate of  whose distance from are , .

The points are , .