What is the larger root of x^2 + 3x - 4 = 0?
Answer and explanation
Correct answer: B. 1
- Step 1: Find two numbers with product -4 and sum -3: they are 1 and -4. Step 2. The equation factorises as (x - 1)(x + 4) = 0. Step 3. The roots are x = 1 and x = -4, so the larger is 1. Answer: 1. Why not the others: -4: That is the smaller root. -1: The sign is wrong: if (x - r) is a factor, the root is +r. 4: That is the smaller root with its sign reversed.
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