# A Angles Type of angle: Acute: An Angle less than 90 degrees Right angle: An angle that is 90 degrees Obtuse angle: An angle more than 90 degrees Straight angle: an angle that is 180 degrees Reflex Angle: An angle that is greater than 180 degrees Binomial A polynomial with two terms which are not like terms. The following are all binomials: 2x 3, 3x5 +8x4, and 2ab 6a2b5.

Circle geometry Inscribed angle: an angle made from points sitting on the circle's circumference. Angle in a Semicircle: An angle inscribed in a semicircle is always a right angle Cyclic Quadrilateral: A "Cyclic" Quadrilateral has every vertex on a circle's circumference. Tangent Angle: A tangent is a line that just touches a circle at one point. It always forms

a right angle with the circle's radius. Degree A unit of angle measure equal to of a complete revolution. There are 360 degrees in a circle. Degrees are indicated by the symbol, so 35 means 35 degrees. Exponents The exponent of a number says how many times to use the number in a multiplication.

In 82 the "2" says to use 8 twice in a multiplication, so 82 = 8 8 = 64 Formula An expression used to calculate a desired result, such as a formula to find volume or a formula to count combinations. Formulas can also be equation involving numbers and/or variables, such as Euler's formula.

Geometrey The study of geometric figures in two dimensions (plane geometry) and three dimensions (solid geometry). It includes the study of points, lines, triangles, quadrilaterals, other polygons, circles, spheres, prisms, p yramids, cones, cylinders, and polyhedral. Geometry typically includes the study of axioms, theorems, and two-column proofs.

How to Add and Subtract Positive numbers Adding Positive Numbers: Adding positive numbers is just simple addition. Example: 2 + 3 = 5 is really saying "Positive 2 plus Positive 3 equals Positive 5" You could write it as (+2) + (+3) = (+5) Subtracting Positive Numbers: Subtracting positive numbers is just simple subtraction. Example: 6 3 = 3 is really saying "Positive 6 minus Positive 3 equals Positive 3"

You could write it as (+6) (+3) = (+3) Inequalities Symbol Words Example > greater than

x+3>2 < less than 7x < 28 You have to pay attention to the direction of an inequality (which way the arrow points)

greater than or equal to 5x-1 If it doesnt look right you have to flip the sign. Multiply (or divide) both sides by

a negative number or Swapping left and right hand less than or 2y + 1 7 equal to The aim is to have x (or whatever the variable

is) on its own on the left of the inequality sign: x>8 or 16>5 Jokes (math) Q: What happened to the plant in math class? A: It grew square roots. Q: How do you make seven an even number? A: Take the s out! Q: Why is a math book always unhappy? A: Because it always has lots of problems Q: What do you call a number that can't keep

still? A: A roamin' numeral. Kite A quadrilateral with two pairs of adjacent sides that are congruent. Note that the diagonals of a kite are perpendicular. Kite: d1 = long diagonal of kite, d2 = short diagonal of kite, Area = () d1d2 Laws of Exponents Exponents are also called Powers or Indices

The exponent of a number says how many times to use the number in a multiplication. In this example: 82 = 8 8 = 64 in words: 82 could be called "8 to the second power", "8 to the power 2" or simply "8 squared" M Definition: Multiplication (often denoted by the cross symbol "", or by the absence of symbol) is the third basic mathematica operation of arithmetic, the others

being addition, subtraction and division (the division is the fourth one, because it requires multiplication to be defined). Example: Number patterns A number pattern is made by adding some value each time. Example: 1, 4, 7, 10, 13, 16, 19, 22, 25, ... This sequence has a difference of 3 between each number. The pattern is continued by adding 3 to the

last number each time, like this: Order of operatoins Order of Operations Do things in Brackets First. Example: yes 6 (5 + 3) = 6 8= 48 no

6 (5 + 3) = 30 + 3 = 33 Exponents (Powers, Roots) before Multiply, Divide, Add or Subtract. Example: yes 5 22 = 5 4= 20 no 5 22 = 102 = 100 Multiply or Divide before you Add or Subtract. Example:

yes 2 + 5 3 = 2 + 15 = 17 no 2 + 5 3 = 7 3= 21 Otherwise just go left to right. Example: yes 30 5 3 = 6 3= 18 no 30 5 3 = 30 15 = 2 Polynomials A polynomial can have constants, variables

and exponents, but never division by a variable. Polynomials can have constants (like 3, -20 or ) variable's (like x and y) exponents (like 2 in . Quotient The answer after you divide one number by another dividend divisor = quotient Example: in 12 3 = 4, 4 is the quotient.

NUMBERS A Rational Number is a real number that can be written as a simple fraction (i.e. as a ratio). Example: 1.5 is a rational number because 1.5=3/2 (it can be written as a fraction. Symmetry The simplest symmetry is Reflection Symmetry (sometimes called Line Symmetry or Mirror Symmetry). It is easy to see, because one half is the reflection of the other half.

With Rotational Symmetry, the image is rotated (around a central point) so that it appears 2 or more times. How many times it appears is called the Order. Point Symmetry is when every part has a matching part: the same distance from the central point but in the opposite direction. Theorem (Pythagoras) a2 + b2 = c2 c is the longest side of the triangle a and b are the other two sides In a right angled triangle:

the square of the hypotenuse is equal to the sum of the squares of the other two sides. measurement Definition: A unit of measurement is a definite magnitude of a physical quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same physical quantity. Any other value of the physical quantity can be expressed as a simple multiple of the unit of measurement. For example, length is a physical quantity.

The meter is a unit of length that represents a definite predetermined length. When we say 10 meters (or 10 m), we actually mean 10 times the definite predetermined length called "meter". Variable A quantity that can change or that may take on different values. Variable also refers to a letter or symbol representing a number. Whole Numbers and Integers

Nonnegative Integers and the numbers 0, 1, 2, 3, 4, 5, etc are whole numbers. Integers are like whole numbers, but they also include negative numbers, but still no fractions. So, integers can be negative {-1, -2,-3, -4, -5, }, positive {1, 2, 3, 4, 5, }, or zero X and Y coordinates x, y coordinates are respectively the horizontal and vertical addresses of any

addressable point. The X coordinate is vertical and the y coordinate is horizontal. Together, the x and y coordinates locate any specific location. Youtube I used YouTube when ever I was confused and did not get how to solve a math problem. Whether studying a few minutes before the test or using it to help me understand the math more it helped a lot.

Here are a few good channels and videos: https:// www.youtube.com/watch?v=ZgFXL6SEUiI https:// www.youtube.com/watch?v=jUAHw-JIo Zero pairs A zero pair is a pair of numbers whose sum is zero. The thought behind zero pairs is to simplify addition and subtraction problems. Take the following expression: 2+3-2+9-3 We can eliminate a few steps needed to simplify this expression (in fact, all of them) by

using zero pairs. To make the zero pairs easier to spot, let's rewrite the expression this way: 2 + 3 + (-2) + 9 + (-3) The zero pairs are 2 and - 2, and 3 and -3. Let's rewrite the expression again, grouping the zero pairs together 2 + (-2) + 9 + 3 + (-3) and get 0+9+0 which is 9. Sources http://www.mathisfun.com/ http://en.wikipedia.org/wiki/Main_Page

Math 9 text book