# General Discussion

### Forum Thread: How to Multiply Two Digit Numbers Quickly

Learn how to multiply two digit numbers in your head. This short cut teaches you to round the numbers to the closes ten so and then multiplying. As a result you have nice easy numbers that you can then add together for the answer.

### Forum Thread: How to Determine if an Equation Is Direct or Inverse Variation.

Is the equation m=5p or c=p/-4 a direct variation or an indirect variation. The video explains how to tell the difference. A chart is provided that helps you classify the equations along with sample problems.

### Forum Thread: How to Determine if a Line Is Perpendicular.

What are perpendicular lines or what is perpendicular? Well perpendicular are two lines that intersect at 90 degree angles. So let's look at a couple of examples of where we will see those. So we have two lines and they are intersecting at 90 degree angles, and I will label it with a little box that represents 90 degrees, and once we know this is 90 degrees we know the other three are 90 degrees because these are lines and lines have a degree of 180 so that would make all four of these 90 deg...

### Forum Thread: How to Find the Side Length of an Isosceles Triangle

Directions for finding the side length of an isosceles triangle. Find the length of side a of an isosceles triangle with a height of 10 and a base of 8.

### Forum Thread: How to Work with Absolute Value

Absolute value explained The absolute value of a number is its distance from zero. Absolute value is written with the following symbol | x | .

### Forum Thread: How to Multiply 2 and 3 Digit Numbers Fast

Use this method to multiply 2 and 3 numbers quickly. With practice you can almost multiply faster than your calculator, and can save you time on a test.

### Forum Thread: How to Multiply Using Lines

I have seen this technique described as "Chinese Multiplication", Japanese Multiplication", Vedic Math Multiplication, and even "Ancient Arabic Multiplication". It is a fun way to multiply numbers using lines. I don't know if you can replace traditional forms of multiplication with this technique, but it does work on all numbers.

### Forum Thread: How to Multiply Using Your Hands

Times table tricks Use your hands to multiply 6,7,8, 9, and 10's. It is easy, and an alternative to times tables.

### Forum Thread: How to Find the Area of a Triangle on a Coordinate Plane.

How do you find the area of a triangle when you don't have a right angle or an altitude?. You can use the coordinates in order to find the area of the triangle.

### Forum Thread: How to Find the Height of a Cylinder

Video: . How to find the height of a cylinder given the volume

### Forum Thread: How to Arc Length of a Circle

Arc Length is the length of the arc that is part of the circumference. The formula for arc length = measure of AB/ 360 2pi radius

### Forum Thread: How to Use the Pythagorean Theorem to Solve Word Problems.

Apply the Pythagorean Theorem Today we are going to look at applying the Pythagorean Theorem.

### Forum Thread: How to Find the Surface Area of a Rectangular Prism.

Video: . Surface Area of a Prism.

### Forum Thread: How to Calculate the Measure of an Inscribed Angle.

Video: . Video covers four Theorems that pertain to Inscribed angles . The four Theorems are as follows.

### Forum Thread: How to Multiply Polynomials with Negative Exponents

Step by step directions for multiplying polynomials with negative exponents. Video: .

### Forum Thread: How to the Sides of a 30-60-90 Triangle,Given Hypotenuse

This video works sample problems in which the hypotenuse of a 30 60 90 triangle is given and trig functions are used to find missing sides.

### Forum Thread: How to Simplify Radicals with Variables

Example problems in which you simplify radicals that have variables. Video: .

### Forum Thread: How to Solve Problems Using the Power of I

Explanation of the "power of i" and how to solve algebra problems involving the "power of i" Video: .

### Forum Thread: How to Graph Quadratic Equations.

How to graph quadratic equations. The example problem graphs a change of direction of a parabola. Video: .

### Forum Thread: How to Multiply Complex Numbers.

Video: . Example problems and step by step directions covering how to multiply complex numbers. Multiplying Complex Numbers| Pattern of i.

### Forum Thread: How to Solve Word Problems with Quadratic Equations

Directions for solving word problems using quadratic equations. Video: .

### Forum Thread: How to Find the Apothem of a Triangle

Step by step directions for measuring the Apothem of a triangle Video: .

### Forum Thread: How to Base Area of a Pyramid

Pyramids are named by the shape of their base. This video reviews how to calculate the area of the base of several pyramids.

### Forum Thread: How to Find Conditional Probability from Tables.

Probability tables help you organize table in order to calculate the likelihood Video: .

### Forum Thread: How to Find Probability Using Venn Diagrams

Directions for finding the probability of events using Venn diagrams Video: .

### Forum Thread: How to Find the Probability of Independent and Dependent Events.

Step by step guide for finding the probability Video: .

### Forum Thread: How to Solve Area of a Circle Word Problems.

Circle word problems Circle word problem 1

### Forum Thread: How to Simplify Complex Fractions

How to simplify complex fractions Complex fractions have a fraction on top of a fraction.

### Forum Thread: How to Use Shortcuts with 30-60-90 Triangles.

Use these shortcuts to help find leg lengths and the hypotenuse of a 30-60-90 triangle. For example,if you are given the leg length how can you quickly find the hypotenuse?

### Forum Thread: How to Work with Vertical Angles in Geometry

Vertical angles are angles that are across the street from each other, so you always look at vertical angles in relationship to each other and in relation to each other. Vertical angles create complementary and supplementary angles.

### Forum Thread: How to Solve Percent Increase Word Problems.

Video gives directions for solving percent increase and decrease word problems: Bob bought a bike for $40, and he sold it for $60. He made a profit of what percent?

### Forum Thread: How to Identify an Equilateral Triangle.

The video covers three rules of an equilateral triangle The first rule is that all three sides of the triangle are congruent which just means they are equal.

### Forum Thread: How to Find the Surface Area of a Sphere

Step by step directions for finding the surface area of a sphere and directions for the volume of spheres

### Forum Thread: How to Find the Perimeter of a Rectangle.

Step by step directions for finding the perimeter of a rectangle. Video: .

### Forum Thread: How to Find the Surface Area of a Prism.

Think of surface area of a prism as the amount of paper needed to wrap a box for Christmas. Step by step directions for finding the surface area of a prism

### Forum Thread: How to Find the Surface Area and Volume of a Sphere

Videos covers the steps and formulas involved in calculating the surace area and volume of a sphere.

### Forum Thread: How to Evaluate Rational Exponents

A review of the rules for evaluating rational exponents. The Math video explains three rules using example problems with radicals..

### Forum Thread: How to Use Complete the Square to Solve Quadratic Functions

Let's talk about, "Completing the square"

### Forum Thread: How to Radius of a Circle

If you are given the area of a circle you can use this information to find the radius. The area of a square is pi radius squared.