Switch to our new maths teaching resources

Slide decks, worksheets, quizzes and lesson planning guidance designed for your classroom.

Lesson details

Key learning points

  1. In this lesson, we will manipulate systems of equations in order to eliminate an unknown. We will look at cases where one equation can be altered to enable elimination by addition or subtraction.

Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

Loading...

5 Questions

Q1.
3x+2y=5 AND 3x-2y=7. If I add these two equations together, which unknown will be eliminated?
both
neither
x
Correct answer: y
Q2.
3x+2y=5 AND 3x-2y=7. If I subtract the two equations, which unknown will be eliminated?
both
neither
Correct answer: x
y
Q3.
3x-5y=17 AND 2x-5y=10. Subtract the first equation from the second equation.
5x=27
x-10y=7
Correct answer: x=7
y=7
Q4.
2x-5y=10 AND 3x-5y=17. Add the two equations together.
10y=27
Correct answer: 5x-10y=27
5x=27
Q5.
3x-5y=17 AND 7x-5y=20. How can I eliminate y from these simultaneous equations?
add
Correct answer: subtract
you can't eliminate y

5 Questions

Q1.
x+y=6. Multiply this equation by 3.
Correct answer: 3x+3y=18
3x+3y=6
3x+y=6
x+y=18
Q2.
x+y=3 AND 2x-y=5 This pair of equations has been transformed. Which of the following are equivalent to the original pair?
2x+2y=6 AND 2x+y=5
Correct answer: 5x+5y=15 AND 14x-7y=35
6x+y=9 AND 10x-5y=25
x+y=7 AND 2x-y=9
Q3.
x+y=3 AND 2x-y=5 This pair of equations has been transformed. Which of the following are equivalent to the original pair?
Option 1
Correct answer: Option 2
Option 3
Option 4
Q4.
2x+5y=9 AND 5x+4y=14. Solve the simultaneous equations.
x=2
Correct answer: x=2 and y=1
y=3 and x=-2
Q5.
10x+5y=5 AND 3x-5y=34. Solve the simultaneous equations.
x=1 and y = -1
x=3
Correct answer: x=3 and y = -5