A wall is made from rectangular bricks so that the right edge of each brick is vertically aligned with the right edge of the brick two rows above
it, as shown at left. Every brick is 6 centimeters tall and 20 centimeters
wide The wall is 8.5 rows tall. The right triangle is drawn so that the
hypotenuse intersects the top right corner of 9 bricks. What is the width
w of the right triangle in centimeters?