for the equation
3x (x-4) - 7
why is 0 one of the roots, it does not make the bracket equal to 0
like, i know 4 is one, but WHY 0
3x (x-4) - 7
why is 0 one of the roots, it does not make the bracket equal to 0
like, i know 4 is one, but WHY 0
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A root of an equation is the value of x for which y = 0 so it's not the bracket that needs to = 0.
First you'll need to multiply out tha bracket to get a quadratic that you can then factorise. Then find what x equals to make the brackets (and therefore y) equal 0.
First you'll need to multiply out tha bracket to get a quadratic that you can then factorise. Then find what x equals to make the brackets (and therefore y) equal 0.
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3x2 - 12x - 7 = 3(x-2)^2 -12 - 7 = 3(x-2)^2 - 19
the roots are x = 2 +/- sqrt(19/3)
the roots are x = 2 +/- sqrt(19/3)