Archive for Algebra

Super Exponents Site

Here is an excellent site about multiplying and dividing monomials. 7th graders if you need a little more help I recommend watching some of the videos. 8th graders, this site is good review from last year. All the videos are hosted on YouTube so you’ll have to access it from home.

You may recognize the video author on some of the examples. 🙂

Comments (3)

Multiplying and Dividing Monomials

7th graders will be learning about how to multiply monomials, ex.  (3x^2)(2x^4). You’ll also learn how to simplify division problems with monomials too. Below are some helpful videos to help you if you need extra help.

8th graders you can watch the videos too and take an extra credit quiz on Quia. Offer available this week only! So do it while the offer lasts.

For mini lessons on multiplying and dividing monomials, check out these videos:

1. Writing Exponents in Expanded Form

[YouTube=http://www.youtube.com/watch?v=X8Q4Ie6dgwU]

2. Multiplying & Dividing Monomials… and common mistakes to avoid

[YouTube=http://www.youtube.com/watch?v=Z6T1BtXKZbs]

Comments (15)

Solving Equations Strategies

We’ve done several methods of solving equations:

1. The cover-up method has you cover up the number and guess-and-check your answers.

2. The drawing method is where you draw a balance beam and write your equation out visually. For example 3x + 2 = 2x + 5 would look like:
x x x + + | x x + + + + +
then you take away variables and or numbers until you have x equal to a number.

3. The algebraic method has you show how you solve the equation. The video by Nutshell Math shows how to solve multi-step equations algebraically.

Strategy: Always check your answer by re-writing the original problem.

Strategy: When checking, wherever there are variables in your equation write parenthesis. Put the answer into the parenthesis and check that both sides are equal.

For example, 2x – 3 = -9, x = -3.

Check:
2( ) – 3 = -9 Write parenthesis where there are variables.
2(-3) – 3 = -9 Then substitute in answer.
-6 – 3 = -9 Simplify.
-9 = -9 Make sure the left-hand side equals the right-hand side.

Warning: If the two sides are not equal, your answer isn’t correct. Check your work in the original problem.

Comments (4)

Candy Math

Happy New Year!

 

If you liked Chocolate Math, then you’ll enjoy this puzzle that I created called Candy Math. Can you figure out why it works?

I’ll give you a hint, I am a math teacher and I love equations.

 

 

 

 

 

YOUR AGE BY CANDY MATH

This is pretty neat.

DON’T CHEAT BY SCROLLING DOWN FIRST!

 

 

It takes less than a minute.

Work this out as you read…

Be sure you don’t read the bottom until you’ve worked it out!

This is not one of those, waste of time things.

It’s fun.

1. First of all, pick the number of times a week that you would like to have candy (more than once but less than 10).

.

.

.

.

2. Multiply this by 4 (just to be bold) .

.

.

.

.

3. Add 9.

.

.

.

.

.

4. Multiply it by 25 — I’ll wait while you get your calculator. (See if you can do it mentally. It’s not that difficult if you think of 25 as one fourth of 100).

.

.

.

.

.

.

5. If you have already had your birthday this year, add 1782 …

If you haven’t, add 1781.

.

.

.

.

.

6. Now subtract the four digit year that you were born.

.

.

You should have a three digit number.

The first digit of this year was your original number (i.e. how many times you want to have candy each week).

The second two numbers are YOUR AGE! (Oh YES, it is!!!!)

.

.

.

.

.

This is the only year (2007) it will ever work, so spread it around while it lasts.

Can you figure out why it works? We’d love to hear your comments.

Leave a Comment

Chocolate Math Puzzle Expires Soon!

A little while ago I sent out a puzzle submitted by Micaela called Chocolate Math. If you can explain how it works, I’ll give you some chocolate. (Open to the first 3 who can explain it). The puzzle and offer expire at the end of 2006. So hurry.

Comments (1)

Chocolate Math

This blog post was submitted by Micaela. Right as I opened her email a friend rang my doorbell and had an article about chocolate. How cool is that! I think I’ll go have a piece of chocolate while you figure this out.

YOUR AGE BY CHOCOLATE MATH

          This is pretty neat.

DON’T CHEAT BY SCROLLING DOWN FIRST!

 

 

It takes less than a minute.

Work this out as you read…

Be sure you don’t read the bottom until you’ve worked it out!

This is not one of those, waste of time things.

It’s fun.

1. First of all, pick the number of times a week that you would like to have chocolate (more than once but less than 10).

.

.

.

.

2. Multiply this by 2 (just to be bold) .

.

.

.

.

3. Add 5.

.

.

.

.

.

4. Multiply it by 50 — I’ll wait while you get your calculator. (See if you can do it mentally. It’s not that difficult if you think of 50 as half of 100).

.

.

.

.

.

.

5. If you have already had your birthday this year, add 1756 …

If you haven’t, add 1755.

.

.

.

.

.

6. Now subtract the four digit year that you were born.

.

.

You should have a three digit number.

The first digit of this year was your original number (i.e. how many times you want to have chocolate each week).

The second two numbers are YOUR AGE! (Oh YES, it is!!!!)

.

.

.

.

.

This is the only year (2006) it will ever work, so spread it around while it lasts.

Can you figure out why it works? We’d love to hear your comments.

Comments (10)