Methods and steps for solving algebraic simultaneous equations
Quiz yourself by thinking what should be in
each of the black spaces below before clicking
on it to display the answer.
Help!
|
|
||||
|---|---|---|---|---|---|
| Simultaneous Equations Addition/Subtraction/Elimination Method | 1. Multiply one or both equations by some number to make the number in front of one of the variables the same in each equation
🗑
|
||||
| Elimination Method Example | 3x + 3y = 24
2x + y = 13
MULTIPLY bottom equation by -3
🗑
|
||||
| Elimination Method Example(Card 2) | Equations become:
3x + 3x = 24
-6x - 3y = -39
🗑
|
||||
| Elimination Method Example (Card 3) | 2. ADD the equations to eliminate the y variable. You get: -3x = -15.
SOLVE for x to get x = 5.
🗑
|
||||
| Elimination Method Example (Card 4) | To solve for y, plug the value x = 5 back into either original equation.
EXAMPLE: 2(5) + y = 13
10 + y = 13
y = 13 - 10, so y = 3.
🗑
|
||||
| Simultaneous Equations Substitution Method | For this method, you need to isolate one of the variables on one side of the equation
🗑
|
||||
| Substitution Method Example (Card 1) | Let's use the equations
x + y = 3
2x + 3y = 8
🗑
|
||||
| Substitution Method (Card 2) | In the first equation, move everything but the x to the right side of the equation to get:
x = 3 - y
🗑
|
||||
| Substitution Method (Card 3) | Now wherever there is an x in the second equation, we can substitute
3 - y. So the equation 2x + 3y = 8 becomes 2(3 - y) + 3y = 8.
🗑
|
||||
| Substitution Method (Card 4) | When we simplify this, we get
6 - 2y + 3y = 8.
This becomes 6 + y = 8 or
y = 8 - 6 = 2
🗑
|
||||
| Substitution Method (Card 5) | Now, to solve for x, simply plug the value for y, which is 2, back into the first equation:
x + 2 = 3. So, x = 1.
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Created by:
wronawoman
Popular Math sets