Download Unit 9 vocabulary

Unit 9 Vocabulary
1.
Angle: two rays with a common endpoint (the
vertex)
2.
Acute angle: an angle that measures less than 90°
3.
Right angle: an angle (formed by perpendicular
lines), that measures exactly 90°
4.
Obtuse angle: an angle that measures greater than
90°, but less than 180°
5.
Equation: a mathematical statement composed of
algebraic and/or numeric expressions set equal to
each other
6.
Unit rate: a ratio between two different units
where one of the terms is 1.
7.
Polygon: a closed figure with at least 3 sides,
where all sides are straight (NO curves)
8.
Triangle: a polygon with three sides and three
vertices
9.
Face: a flat surface of a three-dimensional figure
10. Positive rational numbers: the set of numbers that
can be expressed as a fraction a/b, where a and b
are whole numbers and b ≠ 0, which includes the
subsets of whole numbers and counting (natural)
numbers
11. Volume: the measurement attribute of the amount
of space occupied by matter
12. Area: the measurement attribute that describes
the number of square units a figure or region
covers
13. Congruent: of equal measure; having exactly the
same size or same shape
14. Two-dimensional figure: a figure with two basic
units of measure, usually length and width
15. Three-dimensional figure: a figure that has
measurements including length, width (depth), and
height
16. Side congruency marks: side marks indicating
side lengths of the same measure
17. Angle congruency marks: angle marks indicating
angles of the same measure
18. Height of a rectangular prism: the length of a side
that is perpendicular to both bases
19. Base of a rectangular prism: any two congruent,
opposite and parallel faces shaped like rectangles;
possibly more than one set
20. Properties of triangles: relationship of attributes
within a triangle (EX: an equilateral triangle has all
sides and angles congruent; the sum of the
lengths of two sides of a triangle is always greater
than the length of the third side; the sum of the
angles of a triangle is always 180°; etc.)