Tuesday, May 30, 2006

Julie'sGrowingPost#3

1.) Question # 1 :
What is the difference between an algebraic expression and an equation (hint: One contains this and the other doesn't)? Give an example of both an expression and an equation.

** An algebraic expression has no value until the variables in the epression have been replaced with numbers. To evaluate an expression, replace every variable with a given value for the variable, then evaluate the resulting numerical expression.

** An equation states that one expression is equal to another expression

The difference between an algebraic expression and an equation is that for algebraic expression the variable is not given. You can choose your own variable. In an equation the variable is determined.

** Example
Algebraic Expression

30 + 18 (m)
30 + 18 (12)
30 + 126 = 246

Equation

2n = 10
2n/2 = 10/2
n=5

Question # 2 :
What is a variable and why do we use one in algebra?

** A variable represents the unknown quantity. We use it in algebra because that's what we're solving for.

Question # 3 :
Solve for N


If a square equals two circles and a circle equals one then for the first diagram you have to subtract 4 - 9 to know what a triangle equals to.

4-9=5

a triangle equals to five

Now that we know that a triangle equals to five then we'll be able to solve the next diagram

we add 12 + 5 + 5

12 = 6 squares

5 = 1 triangle

5 = 1 triangle

you add that all up and you get 22 and then you divide 22 by 2 because there are two n's on the other side and you get 11 as an answer. So n=11

Question # 4 :

Solve the following equations. Show all of the steps that are needed.

a.) 3n + 4n + 7 = 2n + 12

7n + 7 = 2n + 12

7n - 2n + 7 = 2n - 2n + 12

5n + 7 = 12

5n + 7 - 7 = 12 - 7

5n = 5

5n/5=5/5

n=1

b.) 8n - (4 + 9) = 11

8n - (4 + 9) = 11
8n - 13 = 11
8n - 13 + 13 = 11 + 13
8n = 24
8n/8 = 24/8
1n = 3
n = 3

c.) (8 - 3)n + 7n + 8 = 4n + 40

5n + 7n + 8 = 4n + 40
5n + 7n + 8 - 8 = 4n + 40 - 40
5n + 7n = 4n
12n = 4n
12 = 4n
12/4 = 4n/4
3 = n

Question # 5 : For this question you need to create a T-chart and a graph to plot your data from this question onto.

You are having a race against your friend, except you are on foot and he is on his bike. You both know that if you are on a bike you will be faster so your friend gives you a head start of 3 minute. If you can run 400m per minute, and your friend can bike 700m per minute, who will be the first to make it to the finish line 2000m away?

you won the race.




Français/French Deutsch/German Italiano/Italian Português/Portuguese Español/Spanish 日本語/Japanese 한국어/Korean 中文(简体)/Chinese Simplified Tagalog/Filipino

3 Comments:

At 7:30 PM, Blogger Mr. Reece said...

Julie you have a small problem with 3c. The answer is not n = 3.

The other minor quibble is with the algebraic expression. I think you mean to say that you can chose the value for the variable in an expression, while the value of the variable is already determined in an equation.

Otherwise it is great

 
At 8:16 PM, Blogger Julie Rose said...

mr. reece i made my corrections

 
At 1:34 PM, Blogger Mr. Reece said...

Your mark is 29/30 due to the minor mistake in 3c

 

Post a Comment

<< Home