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Before a quadratic equation is solved by factorisation, what must one side equal?
AIt must equal one
BIt must equal zero
CIt must equal two
DIt must equal ten
Answer & Solution
Correct answer: B. It must equal zero
1. Factorisation starts from the standard form of a quadratic equation.
2. One side of the equation must be equal to zero.
3. Only then can the rule be used that a product of two factors is zero when one factor is zero.
4. If the right hand side is any other number, that rule gives nothing at all.
_Source: Siyavula Mathematics Grade 11 (Everything Maths, CC BY 4.0), Chapter 2: Equations and inequalities_
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