Question 1157725
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a. x^2+15x=0
b.12x^2+7x-12=0
c.3x^3=27x
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a:

Factorize and use Zero Product Principle.



b:

At least try to factorize, but if not factorable, then use general quadratic solution formula.


c:

Try like this:
{{{3x^3-27x=0}}}
{{{(1/3)(3x^3-27x)=(1/3)0}}}
{{{x^3-9x=0}}} and you should know how to finish from here.