Solve the quadratic equation by factorisation.
Answer
or
The correct answer is or — Hence the two roots are and .
Step-by-step solution
- Write the quadratic as a product of two linear factors: .
- Set each factor equal to zero because a product is zero only if at least one factor is zero.
- Solve giving , and giving .
- Hence the two roots are and .
Common mistake: Incorrectly factoring the quadratic or forgetting to set each factor equal to zero.
Concept tested: Factorisation of quadratic
Published · How this solution was prepared and checked
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