Math 8_Pre
Algebra
Vocabulary to Support ELL
Learning
Real numbers
Natural numbers
Whole number
Integer
Rational number
Irrational
number
s
Terminating and
Non-terminating
decimal
Imperfect
squares
Perfect squares
Can you name the first 15 without looking?
Right Triangle
hypotenuse
Leg
Pythagorean
theorem
Converse of the
pythagorean
theorem
Coordinate grid
Ordered pair
(4,3)
Horizontal Line
Vertical Line
Quadrants on the grid
II
I
I: 1
II: 2
III: 3
III
IV
IV: 4
Translation
One of four transformations: A slide left or right, up or down, OR Both.
Original figure
ABC
The image is a result of a translation 9 left and 8
down ( x - 9, y - 8)
Rotation
Reflection
clockwise
Counter-Clockwise
12
Congruent
Orientation
When naming the
figure can you still
name it going in the
same direction, or has
it’s orientation
changed?
Dilation
What is a dilation in geometry?
A dilation (similarity transformation) is a
transformation that changes the size of a figure.
It requires a center point and a scale factor. The
value of the scale factor determines whether the
dilation is an enlargement or a reduction.
Simply put, dilations always produce similar
figures.
Enlargement
Reduction
Scale factor
Corresponding
side
Corresponding
Angle
similar
proportional
Examples:
Scale factor
that is Greater
than 1
If the scale factor (number you multiply by) used
is greater than 1,
the dilation is an ENLARGEMENT.
●
●
●
●
x 1.5
x2
x 2.5
x3
Scale factor
that is Less than
1
Examples: If the scale factor (number you multiply by) is less than 1, then the
dilation is a REDUCTION.
●
●
●
●
x ½ or .5
x ¼ or .25
x ⅕ or .2
x ⅓ or .333333…
2 x ½ = 1 (see how 2 multiplied by ½ got smaller?)
Parallel Lines
Line p and line m are parallel lines:
line b below are NOT parallel lines.
Line a and
a
p
m
b
Yes,
parallel!
NOT parallel!!!
Supplementary Angle
pairs (sum=180°)
Complementary Angle
pairs (sum= 90°)
Vertical Angles
Transversal line
This transversal crosses two
non-parallel lines.
The transversal is the yellow line because it
crosses or intersects another line or lines. The
white lines are parallel in this case.
Function
Proportional
Mapping a
Function
Rate of change
Similar
triangles on a
Grid
Rise over run
per
Unit rate
Slope
y-intercept
Vertical change
horizontal
change
Undefined slope
m= y₂-y₁
x₂-x₁