Jo wants to work out the solutions of x^2 + 3x – 5 = 0 She says, ‘‘The solutions cannot be worked out because x^2 + 3x – 5 does not factorise to (x + a)(x + b) where a and b are integers.’’ Is Jo correct?

She is not correct. We can solve a quadratic equation in other ways. The easiest way is to use the formula for quadratic equations.x = (-b +/- sq. root (b^2 - 4ac) / 2ax = -3 +/- sq. root 3^2 - 4x -5 / 2 x 1x = -3 +/- sq. root 29 / 2

KA

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