Evaluate x^2 +2x -4 = 0
Using the quadratic formula (-b +- sqrt(b^2 -4ac))/2a we can sub substitute a = 1, b=2 and c = -4 to solve. The answer is x = -1 +/- sqrt(5)
AC
Related Maths GCSE answers
All answers ▸Find the inverse function of f(x)=5/(x-4)
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A shop sells only Apples, Bananas and Mangos. The ratio of Apples to Bananas is 5:11. The next shopper will choose one piece of fruit at random. The probability that they buy a Mango is 0.2. What is the probability that they buy an Apple?