Elimination
Japanese school year: Junior high 2
What you learn
You will learn the elimination method to solve simultaneous equations by adding or subtracting equations to eliminate one variable. This technique provides a systematic way to solve problems involving multiple unknown quantities. Having a firm grasp of linear equations and arithmetic operations with polynomials is beneficial.
Key points
To eliminate one of the two variables, multiply both sides of the equations by suitable numbers so that the coefficients of that variable have the same numerical size.
If the matched coefficients have the same sign, subtract one equation from the other; if they have opposite signs, add the equations together to eliminate that variable.
Once the value of one variable is found, substitute it into either of the original equations to calculate the value of the other variable.
Choose a set to practice.