Find the roots of the following quadratic equation: x^2 +2x -15 =0
The question asks for the roots, this simply means the numbers that could replace x in the equation and the result = 0. There are two ways too do this, firstly either using the Quadratic formula, or my factorising. This equation factors nicely and so we will use method 2 and saw the quadratic formula for more complex equations. You need to make sure the equation is in the form ax^2+ bx + c = 0, and from there your looking for two numbers that add to make b and multiply to make c. In this case 5 and -3. Then when we factoids we get (x+5) (x-3) = 0, meaning our factors are -5 and 3.
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