Grade 8 Math Reference Sheet Geometric Formulas Symbols Pythagorean Theorem ≈ approximately equal to a2 + b2 = c2 ≅ congruent ~ similar Cylinder ∠ angle V = πr h 2
⏐n⏐ absolute value €
Cone V =
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πr 2 h
3
Problem Solving Strategies
Look for a pattern
Sphere Construct a Table
V =
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Tree Diagram
4 πr 3
or V = 1.33πr 3 3
Make a list
Draw a picture
Interior A€
ngles Guess and Check
180(n − 2) Work backwards
Write an equation
Solve a simpler problem
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Add
Subtract
Multiply
Divide
Sum
Plus
More than
Increased by
Added to
Difference
Minus
Less than
Decreased by
Subtracted from
Product
Times
Multiplied by
Doubled
Tripled
Twice
Of
Quotient
Divided by
Per
Page 1 Integers
Properties of Operations Addition:
Same Sign
1. Add the numbers
2. Keep the sign
Different sign
1. Subtract the smaller number from
the larger number.
2. Take the sign of the larger number
a(b + c) = ab + ac -­a(b – c) = -­ab + ac Subtraction:
1. Keep the first number
2. Change the operation to addition
3. Change the sign of the 2nd number
!
4.
Follow addition rules above
Multiplication and Division:
Same Sign: positive
Different sign: negative
LCM
Counter Clockwise Clockwise Slope y 2 − y1
x 2 − x1
1. Start at one, and list multiples of each
number.
2. Identify the first common multiple.
That is the Least Common Multiple.
GCF
1. Find all factors of each number.
2. Circle common factors.
3. Find the greatest (largest #) in common.
That is the Greatest Common Factor. €
Page 2 Making numbers larger: move numbers to the right
Making numbers smaller: move numbers to the left
adjacent angles
alternate interior angles
angle-angle criterion
bivariate data
cluster
coefficient
complementary angles
congruent
coordinate pair
corresponding angles
cube
cube root
dilation
distributive property
domain
equiangular
exponent
exterior angles
function
hypotenuse
image
input
integer
interior angle
inverse operations
irrational number
legs
like terms
line of best fit
linear relationship
negative association
no association
non-linear relationship
order of operations
ordered pair
origin
outlier
output
cube
perfect cube
perfect square
positive association
proportional relationship
Pythagorean theorem
radical
radicand
range
rate of change/slope
rational number
reciprocal
reflection
regular polygon
right triangle
rotation
scale factor
scatter plot
scientific notation
similar
slope
solution
square
square root
supplementary angles
systems of equations
transformation
translation
transversal
triangle
unit rate
vertical angles
volume
x-axis
y-axis
y-intercept
Page 3