radius ←the diameter is all the way across the circle

“ALL YOU EVER WANTED TO KNOW ABOUT A CIRCLE FOR TAKS BUT WERE AFRAID TO ASK.”
A CHORD IS A LINE FROM ONE SIDE OF THE CIRCLE TO THE OTHER.
THE DIAMETER IS A CHORD THAT GOES THROUGH THE CENTER (MIDDLE) OF A CIRCLE.
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THE DIAMETER IS ALL THE WAY ACROSS THE CIRCLE
THE RADIUS IS HALFWAY ACROSS THE CIRCLE.
THE DIAMETER IS ALL THE WAY. (2*R=D)
CIRCUMEFERENCE = π*DIAMETER =2*RADIUS*π
A CIRCLE’S AREA = π*RADIUS*RADIUS = π*R2 = ”PI-R-SQUARED”
COPYRIGHT2009, JAMES DAVID SULLIVAN. ALL RIGHTS RESERVED.