Solve 3x^2 - 4x - 6 = 0.
The at first can seem very challenging and you won't be able to tackle this question quickly using simple factorisation, which you can often do for many questions. It is best in this case then to use the Quadratic Formula, which is extremely helpful for anytime when a Quadratic Equation appears too complex or you just want to check your answers after you've factorised a simpler question. Using the Quadratic Formula won't give you a definitive answer, but will give you two solutions to X and this is really helpful when you study maths at a higher standard like A-Level.
You should start by learning the Quadratic Formula, most exam boards will provide you with this in the exam booklet, but it is very helpful if you can memorise it (although not essential). The formula is: X = [- B (+/-) √ B2 - (4 * A * C) ] / [2 * A]. To solve a Quadratic Formula you must sub in the values in the given equation.
In this case 3x2 - 4x - 6 = 0, where Ax2 - Bx - C = 0.
Subbing this into the formula results in X = [-4 + √42 - (4 * 3 * -6)], all divided by [2 * 3] = 2.23
You must then do the same, but this time with a '-' sign after the '- B'. = 0.900
The result of each answer should give you a different number, these will become the respective solutions to X. The answer can simply be written as: X = 2.230 or 0.900, I would always round by answers to three significant figures if it doesn't specify on the answer booklet.
