Term | Definition |
Central angle | an angle whose vertex is the center of a circle that equals a sum of 360 degrees. |
Chord | a segment that has both endpoints on a circle |
Circle | the set of points in a plane that are all the same distance from a given point called the center |
Circle graph | a graph of data where the circle represents the whole |
Compass | a geometric tool used to draw circles or arcs |
Complementary angles | 2 angles that are complimentary if the sum of their measures is 90 degrees |
Congruent angles | angles that have all the same length |
congruent polygons | 2 polygons that are congruent if they have exactly the same shape and size |
Congruent | sides have the same length |
decagon | a polygon with ten congruent sides. |
Diameter | a segment that passes through the center of a circle and has both endpoints |
Equilateral triangle | a triangle with three congruent sides and three congruent angles. |
hexagon | a polygon with 6 sides |
intersecting lines | 2 or more lines that cross each other |
irregular polygon | a plygon with sides that are not all congruent and/or angles that are not all congruent |
isosceles triangle | a triangle with at least two congruent sides |
Line | a series of points that extends in 2 opposite directions without end |
Midpoint | the point that divides the segment into two segments of equal length |
obtuse angle | an angle with a measure greater that 90 degrees and less than |
obtuse triangle | a triangle with an obtuse angle |
octagon | a polygon with 8 sides |
1 inch is about | 2.5 centimeters. |
1 foot is about | 30 centimeters. |
1 meter is a little longer than | a yard, or about 40 inches. |
1 mile is slightly farther than | 1.5 kilometers. |
1 kilometer is slightly farther than | half a mile. |
1 ounce is about | 28 grams. |
1 nickel has the mass of about | 5 grams. |
1 kilogram is a little more than | 2 pounds. |
1 quart is a little less than | 1 liter. |
1 liter is a little more than | 1 quart. |
Water freezes at | 0°C and 32°F. |
Water boils at | 100°C and 212°F. |
Normal body temperature is about | 37°C and 98°F. |
Room temperature is about | 20°C and 70°F. |
Mass is the | amount of matter in an object. |
Weight is the | pull of gravity on the mass of an object. |
The mass of an object remains the same regardless of | its location. |
The weight of an object changes dependent on | the gravitational pull at its location. |
The perimeter of a polygon is the measure of | the distance around the polygon. |
Circumference is the | distance around or perimeter of a circle. |
The area of a closed curve is the | number of nonoverlapping square units required to fill the region enclosed by the curve. |
The perimeter of a square whose side measures "s" | is 4 times s (P = 4s) |
A square's area with side "s" is | side times side (A = s2). |
The perimeter of a rectangle is the | sum of twice the length and twice the width [P = 2l + 2w |
A rectangle's area is the | product of the length and the width (A = lw). |
The value of pi is the | ratio of the circumference of a circle to its diameter. |
The ratio of the circumference to the diameter of a circle is a constant value, | pi which can be approximated by measuring various sizes of circles. |
The fractional approximation of pi is | 22/7. |
The decimal approximation of pi is | 3.14. |
The circumference of a circle is | the length of the outside of the circle. |
The area of a circle is | the amount of square units needed to cover the entire circle. |
The surface area of a rectangular prism is the | sum of the areas of all six faces ( ). |
The volume of a rectangular prism is computed by | multiplying the area of the base, B, (length x width) by the height of the prism. |
Congruent figures have exactly | the same size and the same shape. |
Noncongruent figures may have the same shape but not | the same size. |
The corresponding angles of congruent polygons have the | same measure, and the corresponding sides of congruent polygons have the same measure. |
The determination of the congruence or noncongruence of two figures can be accomplished by | placing one figure on top of the other or by comparing the measurements of all sides and angles. |
A quadrilateral is | a closed planar (two-dimensional) figure with four sides that are line segments. |
A parallelogram is | a quadrilateral whose opposite sides are parallel and opposite angles are congruent. |
A rectangle is | a parallelogram with four right angles. |
Rectangles have special characteristics | (such as diagonals are bisectors) that are true for any rectangle. |
To bisect means to | divide into two equal parts. |
A square is | a rectangle with four congruent sides or a rhombus with four right angles. |
A rhombus is | a parallelogram with four congruent sides. |
A trapezoid is | a quadrilateral with exactly one pair of parallel sides. The parallel sides are called bases, and the nonparallel sides are called legs. |
If the legs of a trapezoid have the same length, then the trapezoid is | an isosceles trapezoid. |
A kite is | a quadrilateral with two pairs of adjacent congruent sides. One pair of opposite angles is congruent. |
Quadrilaterals can be classified by the number of | parallel sides: |
a parallelogram, rectangle, rhombus, and square each have | two pairs of parallel sides; |
a trapezoid has only one pair of | parallel sides; other quadrilaterals have no parallel sides. |
a rectangle has | four 90° angles; |
a trapezoid may have | zero or two 90° angles. |
a rhombus has | four congruent sides; a square, which is a rhombus with four right angles, also has four congruent sides; a parallelogram and a rectangle each have two pairs of congruent sides. |
The sum of the measures of the angles of a quadrilateral is | 360°. |