5a^3+35a^2-90a

Question

i need help on algebra 2

Answer 1

5a^3+35a^2-90a

 

You haven't told us what you need done with this expression.

 

Each term is factorable by 5a so we can factor that out giving:

 

5a(a² +7a - 18)

 

The quadratic a² + 7a - 18 is also factorable.

Look at the constant -18 ...  see if there are

factors of -18 that add to the coefficient of the

middle term .. 7.

the factors of -18 that add to 7 are (9)(-2)

so a²+7a-18 = (a+9)(a-2)

 

Your final factored form of the expression is:

5a(a-2)(a+9)

 

If you need the zeroes of this they are at

a = {-9, 0, 2}

Answer 2

5a³ + 35a² - 90a

5a(a² + 7a - 14)