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Example Questions
Example Question #11 : Dsq: Calculating An Angle In A Polygon
A nonagon is a nine-sided polygon.
Is Nonagon regular?
Statement 1:
Statement 2:
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Each angle of a regular nonagon measures
Therefore, each of the two statements proves that the nonagon is not regular.
Example Question #14 : Polygons
What is the measure of ?
Statement 1: is an exterior angle of an equilateral triangle.
Statement 2: is an interior angle of a regular hexagon.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
An exterior angle of an equilateral triangle measures . An interior angle of a regular hexagon measures . Either statement is sufficient.
Example Question #267 : Data Sufficiency Questions
Note: Figure NOT drawn to scale.
Refer to the above figure. Is Pentagon regular?
Statement 1:
Statement 2:
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
If a shape is regular, that means that all of its sides are equal. It also means that all of its interior angles are equal. Finally, if all of the interior angles are equal, then the exterior angles will all be equal to each other as well.
In a regular polygon, we can find the measure of ANY exterior angle by using the formula
where is equal to the number of sides.
Each exterior angle of a regular (five-sided) pentagon measures
Statement 1 alone neither proves nor disproves that the pentagon is regular. We now know that one exterior angle is , but we do not know if any of the other exterior angles are also .
Statement 2, however, proves that the pentagon is not regular, as it has at least one exterior angle that does not have measure .
Example Question #261 : Data Sufficiency Questions
Note: Figure NOT drawn to scale.
Refer to the above diagram. Evaluate .
Statement 1:
Statement 2:
xxx
Either alone
Either alone
Refer to the figure below, in which has been constructed, and the top and right sides of the figure have been extended to their intersection to form Rectangle .
Assume Statement 1 alone. Since opposite sides of a rectangle have the same length, . By segment addition, , and, since , by substitution, . Therefore, , and the Pythagorean Theorem can be used to find :
Since opposite sides of a rectangle have the same length, , and by segment addition, . By substitution, , and .
Assume Statement 2 alone. Since , the hypotenuse of right triangle , and , one of its legs, have lengths 15 and 12, respectively, the length of the other leg can be found using the Pythagorean Theorem:
Example Question #151 : Geometry
Note: Figure NOT drawn to scale
Refer to the above figure. Give the length of .
Statement 1:
Statement 2:
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
We can construct perpendicular line segments from to and from to as follows:
is the hypotenuse of a right triangle , so if we can determine the lengths of and , we can use the Pythagorean Theorem to determine the length of .
Assume Statement 1 alone. By segment addition, . Since and are opposite sides of a rectangle, ; similarly, . It follows by substitution that . Since , it follows that , and . However, no additional information exists to find .
Assume Statement alone. By similar reasoning, ; since , , and . However, no information exists to find .
The two statements put together, however, yield both necessary values: and . By the Pythagorean Theorem,
.
Example Question #152 : Geometry
Note: Figure NOT drawn to scale.
Refer to the above figure. What is the length of ?
Statement 1:
Statement 2:
BOTH statements TOGETHER are insufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
To find the length of , we can extend to meet at a point to form two rectangles, as seen below:
Statement 1 gives no helpful information, since the length of , which is not parallel to , has no bearing on that side's length.
If we are given Statement 2 alone, then, as seen in the diagram, from segment addition, , from Statement 2, and from congruence of opposite sides of a rectangle, and . Therefore, , , and .
Example Question #4 : Dsq: Calculating The Length Of A Side Of A Polygon
Given a regular hexagon , what is the length of ?
Statement 1: The hexagon is circumscribed by a circle with circumference .
Statement 2: hs length 12.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Below is a regular hexagon , with its three diameters, its center , and its circumscribed circle, which also has center .
If Statement 1 is true. then the circle, with circumference , has as its diameter , which is 12; this makes the two statements equivalent, so we need only establish that one statement is sufficient or insufficient.
Either way, , the radius of the hexagon, is 6. The six triangles that are formed by the sides and diameters of a regular hexagon are all equilateral by symmetry, so each side of the hexagon - in particular, - has length 6.
Example Question #5 : Dsq: Calculating The Length Of A Side Of A Polygon
Give the length of side of Hexagon .
Statement 1: .
Statement 2: Hexagon has perimeter 42.
BOTH statements TOGETHER are insufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Assume both statements to be true, and examine these two scenarios:
Case 1: The hexagon could have six sides of length 7.
Case 2: The hexagon has four sides of length 7, one of which is , one side of length 6, and one side - - of length 8.
In both situations, and the perimeter of the hexagon is 42:
.
The conditions of both statements would be met in both scenarios, so the two statements together are insufficient.
Example Question #6 : Dsq: Calculating The Length Of A Side Of A Polygon
Give the length of side of Pentagon .
Statement 1:
Statement 2: and both have length 10.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 1 alone states that is congruent to two other sides, but gives no actual measurements. Statement 2 alone gives the actual measurements of two other segments, but without further information, such as how their lengths relates to that of , no information about can be inferred.
Now, assume both statements to be true. From Statement 2, has length 10, and from Statement 2, , which is the same line segment (which can be named after its endpoints in either order), has the same length as . Therefore, .
Example Question #7 : Dsq: Calculating The Length Of A Side Of A Polygon
Give the length of side of Pentagon .
Statement 1: Pentagon has perimeter 50.
Statement 2:
BOTH statements TOGETHER give sufficient information to answer the question, but neither statement ALONE gives sufficient information to answer the question.
BOTH statements TOGETHER do not give sufficient information to answer the question.
Statement 2 ALONE gives sufficient information to answer the question, but Statement 2 ALONE does NOT sufficient information to answer the question.
Statement 1 ALONE gives sufficient information to answer the question, but Statement 2 ALONE does NOT sufficient information to answer the question.
EITHER statement ALONE gives sufficient information to answer the question.
Statement 2 ALONE gives sufficient information to answer the question, but Statement 2 ALONE does NOT sufficient information to answer the question.
Statement 1 alone only gives the perimeter - the sum of the lengths of the sides - but gives no information about the individual sidelengths. (In particular, there is no indication that the pentagon is regular).
Assume Statement 2 alone. and are two names for the same line segment, which can be named after its endpoints in either order. Therefore, .