Solve the inequality x^2 – 5x – 14 > 0.
In order to solve this, the quadratic must be factorised. This means we're trying to get the equation into the form (x+a)(x+b)>0 where a and b are constants where a x b = -14 and a + b = -5. This turns out to be -7 and 2. These constants show us where the graph crosses the axis. We currently have the equation y = (x-7)(x+2) and are looking for solutions when y>0. This means on the graph it will be above the x-axis, i.e. x > 2 and x < -7.
MP
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