Use a compass and a straightedge to construct tangent to circle at point .

Draw a ray from center through point and extending beyond point .

Put the sharp point of the compass on point . Set it to any setting less than the length of , and then draw an arc on either side of , creating points and .

Put the sharp point of the compass on point and set it to a width greater than the distance of . Make a large arc intersecting .

Without changing the compass setting, put the sharp point of the compass on point and draw a second arc that intersects the first. Label the point of intersection with the arc drawn in step 3 as point .

Draw a line connecting points and , creating tangent .

This applet is provided by Walch Education as supplemental material for their mathematics programs. Visit www.walch.com for more information.