What are the solutions of x squared - 6x + 8 = 0?
Answer and explanation
Correct answer: D. x = 4 or x = 2
- Step 1: Find two numbers with sum 6 and product 8: 4 and 2.
- Step 2: So (x - 4)(x - 2) = 0, giving x = 4 or x = 2.
Answer
x = 4 or x = 2.
Why not the others: x = -4 or x = -2: the signs of the roots were reversed. x = 6 or x = 8: the coefficients were taken as the solutions. x = 5 or x = 1: the roots were shifted by one.
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