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acute angle

An angle measuring more than zero degrees and less than 90 degrees

congruent

Having the same size and shape

difference

The amount that remains after one number has been subtracted from another

exponent

A number that tells how many times the base is multiplied by itself

reciprocal

The inverse of a fraction; when multiplied by the original fraction, it results in a product that equals one

vertex (vertices - plural)

The point of intersection for two sides of a plane figure, three sides of a solid figure, or the endpoints of two rays that form an angle.

expression

A combination of numbers and variables connected by one or more operations signs

polygon

Three or more line segments in a plane that forms a closed figure. The line segments never cross but meet at their endpoints.

product

The result of muliplying two or more numbers

range

The difference between the least and greatest values in a set of numbers

scalene triangle

A triangle with sides of different lengths and no two angles are the same

area

Surface space that is measured in square units

perimeter

The distance around a figure

circumference

The distance around a circle (the perimeter of a circle)

straight angle

An angle that measures 180 degrees

obtuse angle

An angle measuring more than 90 degrees and less than 180 degrees

complementary angle

Two angles whose sum equals 90 degrees

diameter

A line segment that passes through the center of a circle and has its endpoints on the circle

sum

The total of two or more numbers being added

quotient

The result of dividing one number by another; the solution to a division problem

mean

The sum of a group of numbers divided by the number of numbers; also known as the average

median

A value found by ordering a group of data from least to greatest and choosing the middle value of the group.

mode

In a group of values, the value that occurs most often

pyramid

A solid figure that has triangles for its sides and a polygon as its base

quadrilateral

A polygon that has four sides

parallelogram

a quadrilateral with two pairs of congruent, parallel sides

rectangle

A parallelogram with four right angles

reflection

A mirror image of a figure shown over a line of reflection

scale drawing

A drawing of an object that is different in size (usually smaller than the original) but keeps the same proportions

octagon

An eight-sided polygon

pentagon

A polygon with five sides

percent

The ratio of a number to 100 (per one hundred); the symbol %

similar figures

Figures that have the same shape but different sizes; their sides are proportional, while their corresponding angles are equal

equilateral triangle

A triangle that has three equal sides and three equal angles

radius

A length that is half the diameter of a circle; the distance from the center of the circle to the circle itself

isosceles triangle

A triangle with two equal sides and two equal angles

right triangle

A triangle with one right angle

supplementary angles

Two angles whose sum is 180 degrees

order of operations

Rules that tell which steps to follow when solving an expression. PEMDAS

rhombus

A parallelogram with all sides equal and congruent. Looks like a diamond or a square that fell over.

square root

A number that when multiplied by itself results in the given number.

proportion

An equation stating that two ratios are equal

simplify

To make a fraction easier to work with by taking out common factors

x-axis

The horizontal number line of a coordinate graph

y-axis

The vertical number line of a coordinate graph

x-coordinate

The value on the x-axis used to locate a point on the coordinate graph. It is the first value in an ordered pair.

y-coordinate

The value on the y-axis used to locate a point on the coordinate graph. It is the second value in an ordered pair.

ordered pair

Two numbers listed in a specific order; it describes a point on the coordinate graph