I need help soving this problem:-6a^4+4a^3-2a^2

Question

i need help with this problem :-6a^4+4a^3-2a^2

Answer 1

I'm with Edwin - you can't solve an expression.  You need an equals sign in the mix (i.e. an equation).  If we have an expression (algebra stuff without an equals sign) we can only simplify.

A good starting place would be to factor.  The number coefficients all share a greatest common factor of 2 (do you see how 2 goes into 2, 4, and 6?) and for the variables the greatest common factor is a^2 (a^2 goes into a^2, a^3, and a^4... don't forget exponents are just a handy way of writing multiplication!)

so if I pull a 2a^2 out of each term, the first term becomes -3a^2, the second term becomes 2a, and the third term becomes -1:

2a^2(-3a^2 + 2a - 1)

Can we factor the trinomial in parentheses?

Not.. really.  I know this because I can look at the discriminant (b^2 - 4ac.. the thing under the square root in the quadratic formula?) and it is negative.  So we're done, since -3a^2 + 2a - 1 doesn't have real roots, so we can't factor it further.

I hope this helps you get started - please check back in if you need more!

Answer 2

Do you mean -6a^4+4a^3-2a^2 = 0, because your original expression had no equal sign.