find the values of x when 3x^2 - 6x - 9
First we will need to factorise the equation.
Start with the 3x^2 term and notice 3 is prime so must have 3x and x terms.
(3x - 9) (x + 1) or (3x + 3) (x - 3)
Setting the brackets to 0 gives us 3x - 9 = 0 and x + 1 = 0 or 3x + 3 = 0 and x - 3 = 0
meaning x = 3 and x = -1
DM
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