## Exterior Angle Theorem

Exterior Angle Theorem For a triangle The exterior angle d equals the angles b plus c. (d = b + c) The exterior angle d is greater than angle b and angle c. (do > bo, do > co) Proof d = b + c : a + b + c = 180° (Because the interior angles of … Continue reading "Exterior Angle Theorem"

## Commutative, Associative, and Distributive Laws

Commutative Laws Commutative Laws say we can swap numbers over and still get the same answer. Commutative Laws for Addition a + b = b + a Commutative Laws for Multiplication a × b  =  b × a From these laws it follows that any finite sum or product is unaltered by reordering its terms … Continue reading "Commutative, Associative, and Distributive Laws"

## Finding an Angle in a Right Angled Triangle

We can find an unknown angle in a right-angled triangle, as long as we know the lengths of two of its sides. Use Sine, Cosine or Tangent! Use SOHCAHTOA to help you, like this: How to Finding an Angle in a Right Angled Triangle 1. find the names of the two sides we know Adjacent … Continue reading "Finding an Angle in a Right Angled Triangle"

## Complex Numbers

Imaginary number Imaginary number (when squared give a negative result) i is the unit of imaginary number which is square root of -1 i = √-1, because i2=-1 So, (7i)2 = -7 Definition of Complex Number A Complex Number is a combination of a Real Number and an Imaginary Number Either Part Can Be Zero … Continue reading "Complex Numbers"

## Directly and Inversely Proportional

Directly Proportional Directly proportional: when one amount increases, another amount increases at the same rate. The symbol for “directly proportional” is ∝ Inversely Proportional Inversely Proportional: when one value increases, at the same rate that the other decreases. Examples   Directly Proportional Inversely Proportional Have more workers You pay more Work time is shorter How … Continue reading "Directly and Inversely Proportional"

## Irregular Polygon

Regular polygon is a polygon that has all angles equal and all sides equal. So, regular polygon has a = b = c = d = e, and ∠v = ∠w =∠x = ∠y = ∠z Definition of Irregular Polygon Irregular polygon is a polygon that does not have all sides equal and all angles … Continue reading "Irregular Polygon"

## Decimals, Fractions, and Percentages

Definition Decimals, Fractions & Percentages are different ways of showing value Examples Percent Decimal Fraction 1% 0.01 1/100 5% 0.05 5/100 10% 0.1 10/100 25% 0.25 25/100 50% 0.5 50/100 75% 0.75 75/100 100% 1 100/100 125% 1.25 125/100 150% 1.5 150/100 200% 2 200/100 Conversions Base Form Decimals Fractions Percentages Decimals – 1) multiply … Continue reading "Decimals, Fractions, and Percentages"