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
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All answers ▸How do I solve simultaneous equations given a linear and a quadratic equation?
Solve the simultaneous equations: 5x + y = 21, x - 3y = 9
Factorize x^2 + 4x -5 and hence find the roots of the quadratic equation y = x^2 + 4x - 5.
Solve the simultaneous equations 3x + 2y = 12 and 10y = 7x + 16