Seventh Grade Math Vocabulary

Acute TriangleA triangle whose angles all measure less than

90°

Examples

Golden acute

triangle

36

7272

Area of Complex Shapes

The number of square units needed to cover a given surface

Divide the shape into shapes whose areas are easy to calculate

and then add (or subtract) to find the area of the given shape

Example

The area of the given shape is:1500 + 3000 = 4500 square units

1500

3000

Area ofIrregular shapes

The number of square units needed to cover a given surface

Count the number of whole square units and combine partial square units together to get a total area

Examples

The area is approximately 10 units² The area is approximately 32 units²

Box & Whisker PlotA graph that shows how far apart

and how evenly data are distributed

Example

68 is the median, 52 is the lower quartile, 87 is the upper quartile

18 27 34 52 54 59 61 68 78 82 85 87 91 93 100

Equiangular TriangleA triangle with three congruent angles

(and also three congruent sides)

60 60

60

Equilateral TriangleA triangle with three congruent sides

(and also three congruent angles)

Examples

Exponent Notation A number written with a base an exponent

Examples

32 8

211Base

Exponent

= 64

Exponent The number that indicates how many times

the base is used as a factor

Examples

34 4 4 4 24 4 4

44 4 4 4 4 28 8 8 base

Inequalities(number line)

The graph of a mathematical sentence showing the relationship between quantities that are not equal,

using <, >, <, >, or

Examples

2x

4x

2x

2x

IntegerThe set of whole numbers and their opposites

Examples

Integers

120

2 2

Use the remaining integers to Make every circle add to zero

Isosceles Triangle A triangle with (at least) two congruent sides

The two congruent sides are called legsThe third side is the base

The angle formed by the legs is the vertex angle

Examples:

legleg

base

Vertex angle

Linear Equation An equation that can be represented as a line

on the coordinate plane

Examples

2x y 3y x 2 3y x

Multi-step EquationsAn equation where you have to do more than one

operation in order to find the solutions

Examples

2 3 17

2 20

10

x

x

x

3( 1) 15

3 3 15

3 12

4

x

x

x

x

5 2 18

3 18

6

x x

x

x

Obtuse Triangle

A triangle containing exactly one obtuse angle(an angle greater than 90 degrees)

90

OppositeTwo numbers (represented by points on the

number line) that are the same distance from zero and are on opposite sides of zero

Examples

1 1

and are opposites2 2

The opposite of 0 is 0

4 and -4 are opposites

8 and -8 are opposites

Percents (above 100, below 1)A percent is a ratio that compares a number to 100

Percent means “per hundred”Examples

11/10

110%

+1

.

.7 10 7.7%

100 10 1000

A percent above 100 means you have more than a whole: 1 5 250

2 250%2 2 100

Pi (approximation)

The ratio of the circumference of a circle to the length of its diameter

Examples

C

d 12.56C cm

4d cm

12.563.14

4

10d cm

31.43.14

10

31.4C cm

3.14159265358979323846264338327950288419716939937510582...

Rational NumbersAny number that can be expressed as a ratio

where a and b are integers and b 0Decimals representing rational numbers

either terminate or repeat

Examples

a

b

( is irrational)

66

1

1.3

3

Real Numbers

Rational NumbersIrrational numbers

Integers

Whole numbers

Natural numbers

00

1

2

3

2

3

.1

19

.

22

9

Regular Polygon A polygon in which all sides and all angles are congruent

Examples

Equilateral triangle

square

pentagon

hexagon

heptagonoctagon

nonagon

decagon

Right TriangleA triangle with exactly one right angle

Examples

90 90

Scale FactorThe common ratio for pairs of

corresponding sides of similar figures The ratio used to enlarge or reduce objects

Examples

The scale factor is 2

4

63

8

5

10

Models: if a car is 204” in length and the length of a model of the car is 12” long, the scale factor would be

12 1

204 176 8 10

23 4 5

Scalene TriangleA triangle with no congruent sidesIts sides are all different in length

(Its angles are also all different in size)Examples

a b c

1014

20

Scatter Plots A graph of plotted points that attempts

to show a relationship (correlation)between two variables

Examples

This data shows a positive correlation:

As x increases, so does y

This data shows a negative correlation:

As x increases, y decreases

This data shows no correlation

SimilarityFigures that have the same shape, but not necessarily the same size

Examples

Similar Similar

6565

2525

Similar polygons have congruent corresponding angles

Similar polygons havecorresponding sides that formequivalent ratios (proportions)

2

54

102 5

4 10