The problem
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Why is there two answer to this question.
Answer provided by our tutors
First, the equation 'x(x + 2)=0' is a quadratic equation so two answers at most are expected.
Zero Product Theorem states that the product of two factors is zero then at least one of the two factors must be zero.
In our case the two factors are: 'x' and 'x + 2'.
So, we have:
'x = 0' (one answer is x = 0) and 'x + 2 = 0'
Solving 'x + 2=0' we find x = -2 (second answer is -2).
Another way of determining the solutions is by graphing the equation:
y = x(x + 2) and finding the x-intercepts:
The x-intercepts are x1 = -2 and x2 = 0