1 / 8

Substitution

Substitution. Algebraic expressions are very often used to describe a situation in general terms. This means that the expression has a variable that can change and the value of the expression depends on the input for this variable. Substitution means replacing a variable with a number.

amara
Download Presentation

Substitution

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Substitution

  2. Algebraic expressions are very often used to describe a situation in general terms. This means that the expression has a variable that can change and the value of the expression depends on the input for this variable.

  3. Substitution means replacing a variable with a number. You then work out the value of the resulting expression using the correct order of operations (BEDMAS). So what does Substitution mean? Algebraic expressions are very often used to describe a situation in general terms. This means that the expression has a variable that can change and the value of the expression depends on the input for this variable.

  4. Example Let us think that the formula tells a farmer how many cows he can have where is the number of paddocks he has. How many cows could he have if he had 3 paddocks? How about 12? Is there a limitation to this rule? Algebraic expressions are very often used to describe a situation in general terms. This means that the expression has a variable that can change and the value of the expression depends on the input for this variable.

  5. More examples If , and find the values of these expressions: Algebraic expressions are very often used to describe a situation in general terms. This means that the expression has a variable that can change and the value of the expression depends on the input for this variable. 3 4 10 -3

  6. What you need to be careful with! • Using ‘hidden brackets’ • e.g. If p =-3 and q=6, then for • Negative numbers • e.g. For • Note: use brackets around the negative number (-3)

  7. Use formula and substitution applied to word (application) problems Fish and Chips order F = Number of pieces of Fish C = Number of scoops of Chips Our formula (rule) is $ = 2F + 1.5C where $ = Total Cost spent 1) How much does one piece of fish cost? 2) How much does one scoop of chips cost? 3) How much does 2 fish and 2 scoops of chips cost? 4) 4 fish and 3 scoops? 5) If I had spent $9.00 what did I buy? 6) If I spent $15.00 what could I buy?

More Related