# display, explain, and justify mathematical ideas and arguments using precise mathematical language in written or oral communication

### Popular Tutorials in display, explain, and justify mathematical ideas and arguments using precise mathematical language in written or oral communication

#### What are Similar Figures?

Looking at two figures that are the same shape and have the same angle measurements? You have similar figures! Learn all about it in this tutorial!

#### What are Rates and Unit Rates?

Can you do 100 sit-ups in 2 minutes? That's a rate! Driving a car going 40 miles per hour? That's a unit rate! Watch this tutorial to learn about rate and unit rate (and the difference!).

#### What is a Scale Drawing?

Without a blueprint, it would be really hard to construct a building. Without a road map, you'd be lost! Scale drawings make it easy to see large things, like buildings and roads, on paper. Even a GPS uses scale drawings! Check out this tutorial to learn all about scale drawings.

#### What's the Constant of Variation?

The constant of variation is the number that relates two variables that are directly proportional or inversely proportional to one another. But why is it called the constant of variation? This tutorial answers that question, so take a look!

#### How Do You Use a Tree Diagram to Count the Number of Outcomes in a Sample Space?

When you're trying to figure out all the possibilities from different options, it can be helpful to make a tree diagram. In this tutorial, you'll see how to use a tree diagram to figure out how many different outfits can be created from the possible shirts, bottoms, and shoes given. Check it out!

#### How Do You Find the Probability of a Simple Event?

Working with probabilities? Check out this tutorial! You'll see how to calculate the probability of picking a certain marble out of a bag.

#### How Do You Find the Mean of a Data Set?

Mean is just another name for average. To find the mean of a data set, add all the values together and divide by the number of values in the set. The result is your mean! To see an example of finding the mean, watch this tutorial!

#### How Do You Compare the Mean and Median of Data Sets Using a Line Plot

The mean and median can help you better understand a data set. Check out this real world example involving finding and comparing the mean and median of multiple data sets.

#### What is a Sample Space?

In an experiment, it's good to know your sample space. The sample space is the set of all possible outcomes of an experiment. Watch this tutorial to get a look at the sample space of an experiment!

#### What is Experimental Probability?

Do real life situations always work out the way your mathematical models tell you they should? No! This tutorial describes how experimental probability differs from theoretical probability.

#### What are Like Terms?

Combining like terms together is a key part of simplifying mathematical expressions, so check out this tutorial to see how you can easily pick out like terms from an expression

#### What's a Rational Number?

There are lots of different kind of numbers that you should know about, and that includes rational numbers. Check out the tutorial!

#### How Do You Rewrite Subtraction as Addition?

Subtracting a positive is the same thing as adding a negative. Subtracting a negative is the same as adding a positive. Get a closer look with this tutorial!

#### What is the Formula for Simple Interest?

Interest is found in a bunch of places: savings accounts, mortgages, loans, investments, credit cards, and more! Watch this tutorial and learn how to calculate simple interest!

#### What's a Percent of Change?

Lots of things in this world change their value such as cars, video games, and computers. When something either increases or decreases in value, it can be useful to know the percent of that change in value. To figure out that percent, you'll need the percent of change formula. Learn it with this tutorial!

#### How Do You Figure Out Sales Tax?

Going shopping can be tons of fun, but things can go sour when you get to the register and realize that the sales tax puts you over your budget. Always stay under budget by figuring out your total cost BEFORE you hit the check out. Watch this tutorial and learn how to calculate sales tax!

#### What's the Direct Variation or Direct Proportionality Formula?

Ever heard of two things being directly proportional? Well, a good example is speed and distance. The bigger your speed, the farther you'll go over a given time period. So as one variable goes up, the other goes up too, and that's the idea of direct proportionality. But you can express direct proportionality using equations, and that's an important thing to do in algebra. See how to do that in the tutorial!

#### How Do You Solve and Graph a Two-Step Inequality?

Solving an inequality for a variable? Just perform the order of operations in reverse! Don't forget that if you multiply or divide by a negative number, you MUST flip the sign of the inequality! That's one of the big differences between solving equalities and solving inequalities.

#### What is a Circle Graph?

A circle graph is just one of many ways to display data. This tutorial teaches you the ins and outs of circle graphs!

#### How Do You Determine Which Operations to Use in a Word Problem?

Turning a word problem into a math problem you can solve can be tricky. Luckily, there's some key words to look out for in a word problem that help tell you what math operation to use! This tutorial shows you some of these key words to look for in a word problem.

#### How Do You Solve a Two-Step Equation?

Becoming a pro at solving equations takes practice! Follow along with this tutorial to see an example of solving an equation for a variable.

#### What is the Percent Equation?

Taking a percent of a number? Percent equations can be very helpful in solving such a problem, but what are percent equations? Watch this tutorial to learn about percent equations!

#### What is the Formula for Compound Interest?

Things like bank accounts, loans, investments, and mortgages are a part of life, and almost always, interest is involved. Sometimes, you need to deal with compound interest, so it would be good to know the formula for it! In this tutorial, you'll see the formula for compound interest. Take a look!

#### How Do You Find a Missing Angle in a Right Triangle?

Trying to find a missing interior angle measurement in a triangle? See if you're working with a special type of triangle such as an equilateral or isosceles triangle. If you are, that knowledge can help you. In this tutorial, see how identifying your triangle first can be very helpful in solving for that missing measurement. Take a look!

#### What are Acute, Obtuse, Right, and Straight Angles?

Did you know that there are different kinds of angles? Knowing how to identify these angles is an important part of solving many problems involving angles. Check out this tutorial and learn about the different kinds of angles!

#### What are Complementary Angles?

Do complementary angles always have something nice to say? Maybe. One thing complementary angles always do is add up to 90 degrees. In this tutorial, learn about complementary angles and see how to use this knowledge to solve a problem involving these special types of angles!

#### What are Supplementary Angles?

Knowing about supplementary angles can be very useful in solving for missing angle measurements. This tutorial introduces you to supplementary angles and shows you how to use them to solve for a missing angle measurement. Take a look!

#### What are Vertical Angles?

Vertical angles have a very special quality. They are always congruent to one another! Check out this tutorial to learn about and see how to identify vertical angles!

#### How Do You Find the Area of a Composite Figure?

Composite figures are just a combination of simpler figures in disguise! In this tutorial, you'll see how to break down a composite figure into simpler figures. Then, see how to find the area of each of those individual figures to find the area of the entire composite figure. Watch the whole process in this tutorial!

#### What is an Unbiased Sample?

When you're trying to learn about a population, it can be helpful to look at an unbiased sample. An unbiased sample can be an accurate representation of the entire population and can help you draw conclusions about the population. This tutorial introduces you to unbiased sampling!