S French Lesson Notes 10C3 Simultaneous Equations 25.01.2012
Simultaneous Equations (B Grade)
4x + y = 17 2x + y = 9
Step 1: Check the x or y coefficient is the same, if not balance them Step 2: Subtract or Add one equation from the other to eliminate
Step 3: Solve this equation Step 4: Substitute this value into one of the original equations
Step 5: Solve this equation
1
Simultaneous Equations (Subtract to Eliminate y)
5x + 2y = 13 x + 2y = 9
Step 1: Check the x or y coefficient is the same, if not balance them Step 2: Subtract or Add one equation from the other to eliminate
Step 3: Solve this equation Step 4: Substitute this value into one of the original equations
Step 5: Solve this equation
2
3
Simultaneous Equations (Add to eliminate y)
3x + 2y = 11 2x 2y = 14
Step 1: Check the x or y coefficient is the same, if not balance them Step 2: Subtract or Add one equation from the other to eliminate
Step 3: Solve this equation Step 4: Substitute this value into one of the original equations
Step 5: Solve this equation
Simultaneous Equations (Subtract to eliminate y)
3x 4y = 17 x 4y = 3
Step 1: Check the x or y coefficient is the same, if not balance them Step 2: Subtract or Add one equation from the other to eliminate
Step 3: Solve this equation Step 4: Substitute this value into one of the original equations
Step 5: Solve this equation
4
Simultaneous Equations (change 1 equation) Step 1: Check the x or y coefficient is the same, if not balance them
5x + 2y = 4 4x y =11
Step 2: Subtract or Add one equation from the other to eliminate
Step 3: Solve this equation Step 4: Substitute this value into one of the original equations
Step 5: Solve this equation
Simultaneous Equations (change 1 equation)
2x + 3y = 19 6x + 2y = 22
Step 1: Check the x or y coefficient is the same, if not balance them Step 2: Subtract or Add one equation from the other to eliminate
Step 3: Solve this equation Step 4: Substitute this value into one of the original equations
Step 5: Solve this equation
5
Simultaneous Equations (change both equations) Step 1: Check the x or y coefficient is the same, if not balance them
4x + 3y = 27 5x 2y = 5
Step 2: Subtract or Add one equation from the other to eliminate
Step 3: Solve this equation Step 4: Substitute this value into one of the original equations
Step 5: Solve this equation
Simultaneous Equations Questions
1)
x + 3y = 9 x + y = 6
2)
2x + 5y = 16 2x + 3y = 8
3)
3x y = 9 5x +y = 11
4)
3x + 2y = 16 x 2y = 4
5)
4x + 3y =37 2x + y = 17
6)
x + 3y = 7 2x y = 7
7)
3x + 5y = 15 x + 3y = 7
8)
3x 2y = 3 5x + 6y = 12
9)
2x + 5y = 15 3x 2y = 13
10)
2x + 3y = 20 5x + 7y = 71 6
Simultaneous Equations Answers
1)
x = 4.5 y = 1.5
2)
x = 2 y = 4
3)
x = 2.5 y = 1.5
4)
x = 5 y = 0.5
5)
x = 7 y = 3
6)
x = 4 y = 1
7)
x = 2.5 y = 1.5
8)
x = 1.5 y = 0.75
9)
x = 5 y = 1
10)
x = 3 y = 8
7