All SSAT Upper Level Math Resources
Example Questions
Example Question #311 : Geometry
A square on the coordinate plane has as its vertices the points
. Give the equation of a circle inscribed in the square.
Below is the figure with the circle and square in question:
The center of the inscribed circle coincides with that of the square, which is the point
. Its diameter is equal to the sidelength of the square, which is 8, so, consequently, its radius is half this, or 4. Therefore, in the standard form of the equation,,
substitute
and .
Example Question #252 : Coordinate Geometry
Give the area of the circle on the coordinate plane whose equation is
.
The standard form of the equation of a circle is
where
is the radius of the circle.We can rewrite the equation we are given, which is in general form, in this standard form as follows:
Complete the squares. Since
and , we do this as follows:
, and the area of the circle is
Example Question #311 : Geometry
Which of the following is the equation of a circle with center at the origin and area
?
The standard form of the equation of a circle is
,
where the center is
and the radius is .The center of the circle is the origin, so
, and the equation is
for some
.The area of the circle is
, so
We need go no further; we can substitute to get the equation
.Example Question #531 : Ssat Upper Level Quantitative (Math)
Which of the following is the equation of a circle with center at the origin and circumference
?None of the other responses gives the correct answer.
None of the other responses gives the correct answer.
The standard form of the equation of a circle is
,
where the center is
and the radius is .
The center of the circle is the origin, so
.The equation will be
for some
.The circumference of the circle is
, so
The equation is
, which is not among the responses.Certified Tutor
All SSAT Upper Level Math Resources
