Graph the coordinate plane and locate the points *A* and *B.* lies on vertical gridline.

Since triangle *ABD* has right angle at *B*, is perpendicular to .

Find the length of from the graph.

Since is the shorter leg, is the longer leg.

Triangle *ABD* is a 30°- 60°- 90° triangle.

The 30°- 60°- 90° triangle has the property that the length of its longer leg is

times to the length of the shorter leg.

(Substitute *AB* = 3)

(Multiply)

The *x*-coordinate of the point *D* is or 13.2.

The *y*-coordinate of the point *D *is as same as *y*-coordinate of the point *B*.

The coordinates of the point *D *are or about .

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