Translate into mathematical equation. Select variables to use. ( Translating to Algebra).

Question

l. What is the total weight of a trailer loaded with lumber, if the trailer weighs 800 pounds and the lumber weigh 10 pounds per linear foot?

2. At the mall, soda costs $1.50 and refills are 75 cents. How much does it cost to but a soda and have refills?

Answer 1

Choose whatever variables you want, but make sure you "define" them. 

 

 

1. Let's say T = total weight of the trailer.  Let's say x = feet of lumber.

 

 

Hypothetically, if you have 5 feet of lumber, your weight is 10 * 5 --> 50

If you have 7 feet of lumber your weight = 10 * 7 --> 70

See how the weight of the lumber will change, depending on how many feet you have?

 

 

The total weight of the trailer is a specified amount (the 800 lbs; it's not going to change.  This is called the base value. ) PLUS the weight of all the lumber.  Since you don't really know HOW many feet of lumber you have, use the variable x. 

 

T = 800 + 10 x  

 

 

 

 

2. Let C = total cost.   The cost is going to be the soda you buy, plus however many refills you get (each refill is 75 cents). The cost of the soda isn't going to change, it'll always be $1.50. 

 

 

Just like the example above, if you get 1 refill it will cost you $0.75.  

2 refills = $0.75 * 2

3 refills = $0.75 * 3

 

and so on.  Use a variable like x, to represent the number of refills.

 

Try to see if you can get this one on your own, but let me know if you have questions!

Answer 2

800 + 10*F where F is the number of linear feet of lumber

 

1.50 + 0.75*r where R is the number of refills