# ch 8 math

The flashcards below were created by user deley on FreezingBlue Flashcards.

1. (1) area of a triangle
(2) area or a rectangle, parallelogram
(3) area of a trapetzoid
(4) circumference of a circle 2 formulas
(5) what is pi ?
(6) area of a circle
• (1) triangle A = 1/2bh
• (2) rectangle or parallelogram A = bh or lw
• (3) trapezoid A = 1/2(b1 + b2)
• (4) C = pi (r)(r) or C = pi(d)
• (5) pi= 22/7 or pi = 3.14
• (6) circle area A = pi (r)(r)
2. 1. natural numbers
2. whole #
3. rational #
4. irrational #
5. real #
6. integers
• 1. natural = 1,2,3,4....
• 2. whole = 0,1,2,3.....
• 3. rational = number that can be written as fractions 1/2,3/4,22/7, -2/3 ......
• 4. irrational = pi - 3.14 , .666666...., repeating decimals
3. concept map of plane figures from polygon to square
• parallelagram ------ rhombus \
• / \ square
• polygon -- quadirlaterial rectangle /
• \ trapezoid
4. square roots are?
the inverse of squaring a number

• 52 is 25 , square root of 25 is 5
• 72 is 49 , square root of 49 is 7
5. (1) what is the Pythagorean theorem?
(2) in a right triangle the shortest sides are the legs
(3) the side opposite the right angle is the hypotenuse

(d) find the length of the hypotenuse of the triangle if the leg lengths are 12 and 9
• (1) a2 + b2 = c2
• (d) C2 = a2 + b2
• C2 = 122 + 92
• = 144 + 81
6. 3-D figures
what is a face
edge
prism
heigth of a prism
cube
cylinder
cone
pyramid
sphere
pyramid
• face is a flat surface shaped like a polygon
• edge is an intersection of two faces
• prism is a 3-D figure with 2 parallel and congruent polygon faces
• heigth of a prism is the length of the perpendicular segment that joins the bases
• cube is a rectangular prism with square faces
• cylinder has 2 cingruent parallel circular bases
• cone- 1 circular base and 1 vertex
• pyramid 3-D figure , triangular faces and 1 vertex
• sphere is a set of points in space that are equal distance from a center point
7. surfacce area of a shape: cone pyramid, prism .... is
• surface area is the sum of all areas of its faces
• find the area of its net, area of all faces
8. (1) volume is

(2) volume of a rectangular prism

(3) volume of cylinder
• (1) 3-D figure.
• area of base X height = X3
• (2) = Bh
• = lwh
• (3) = Bh
• = (pi)r2h
 Author: deley ID: 4935 Card Set: ch 8 math Updated: 2010-01-24T16:55:48Z Folders: Description: area formulas Show Answers: