Lista de exercícios do ensino médio para impressão
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

×
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:
a)

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

 



answer: a) 125° b) 145°
×
AB is the diameter of the circle whose center is O and the triangle ABC is inscribed in. The quotient $\,\dfrac{s}{S}\,$ where the area $\,s\,$ of the triangle ACO is divided by the area $\,S\,$ of the triangle COB is:
a)
$\,\dfrac{5}{4}\,$
b)
$\,\dfrac{4}{3}\,$
c)
$\,\dfrac{3}{4}\,$
d)
$\,1\,$
e)
$\,\dfrac{\sqrt{3}}{2}\,$
triiangle ACB inscribed in the circle whose center is O

 



answer: (D)
×
(FESP - 1991) An equilateral triangle ABC is inscriibed in a circle whose radius is 6 cm length. The triangle is intercepted by a diameter MN of the circle, forming a trapezoid, as shown in the picture below. We can say that the quotient of the triangle ABC area divided by the trapezoid APQC area is:
a)
$\,\dfrac{5}{4}\,$
b)
$\,\dfrac{9}{5}\,$
c)
$\,\dfrac{9}{8}\,$
d)
$\,\dfrac{9}{4}\,$
e)
$\,\dfrac{8}{5}\,$
circle with an equilateral triangle inscribed in

 



answer: (B)
×
In the following picture:
$\,\overline{PP'}\,$ is the diameter of the sphere whose center is $\,O\,$, $\;M\,$ é is the center of a intersection with a plane perpendicular to $\,\overline{PP'}\,$. Also the measures are $\,\overline{AP}\,=\,6\,cm\;$ and $\,\overline{AP'}\,=\,8\,cm\;$. Calculate the area of the cicle whose center is $\,M\,$.
esfera e secção plana

 



answer: The area is $\,\frac{\,576\,\pi\;}{\;25\;}\;cm^2$
×
Other math tests:
circumference
circle