Lista de exercícios do ensino médio para impressão
The length of the arc $\,\stackrel \frown{AB}\,$, as in the picture, is 22 cm and O is the center of the circle. The perimeter of the circle (circumference) is:
circle with short arc AB 45 deg
990 cm
67 cm
176 cm
88 cm
none of these answers


answer: Answer (C)
What is the radius of the following circle which center is O,
given that:
AB = 3x - 3 and
OA = x + 3.
circle which center is O and diameter is AB


answer: 12

Find x in the following cases:
a) s is perpendicular to $\;\overline{AB}\,$
circle of center O with chord AB and line s perpendicular to AB
b) $\,\overline{PA}\,$ and $\,\overline{PB}\,$ are tangent segments to the circle
external point P intersection of two tangent segments to the circumference with center O


answer: a) 6b) 9
The circles in the picture are externally tangent. The distance between the centers $\,\overline{OC}\,$ is 28 cm and the difference between their radii is 8 cm. Find the length of each radius.
two circles that are tangent to each other externally


answer: 18 cm and 10 cm
Knowing that O is the center of the circle, find x in the following cases:

circle with the center O and two intersecting lines in O
circle with center O and a tangent and a diameter drawn


answer: a) 125° b) 145°
Other math tests: