Solve 2x^2 + 6x + 4 = 0 for x using the quadratic formula.

When you look at the question you can see that you have been given a quadratic equation. These tend to come in the format ax^2 + bx + c = 0. Remember it may not always be x, it could be y or z, or another letter. The first thing is to recognise that in this case a=2, b=6 and c=4. This will help when inputting into the quadratic equation, make sure you show how you worked it out rather than inputting it directly into the calculator as you will get marks for your working.  The quadratic is something that you should be given in the exam, but you will need to know how to use it. When using it you need to be careful with the positive and negative signs, particularly, the –b at the start. Using the formula you can input the numbers and show that x = -2 or x= -4.

PN

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