Solve 3x² + 6x – 2 = 0. Give your solutions correct to 2 decimal places [calculator paper]

We have a quadratic equation since the highest power of x is 2. Therefore, we can use the quadratic formula, which we recall to be: x = [- b ± √(b² - 4ac) ] / 2a In accordance with the formula, we set a = 3, b = 6, and c = -2. Substituting these values in gives x = [-6 ± √(6² - 4(3)(-2))] / 2(3) = [-6 ± √(36 - (-24))] / 6 = [-6 ± √60] / 6 = (using calculator) = -2.29 or 0.29 (to 2 d.p.) Hence the solutions to the given equation are given by x = -2.29 and x = 0.29

TD

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