Question

solve the equation 8x^3+4x^2-18x-9=0 algebraically for all values of x. help pleaseeee!!

Answer 1

factor 4x^2 out of first two terms: 4x^2*(2x+1)
factor (-9) out or other two terms: (-9)*(2x+1)
Factor (2x+1) out of both terms you get:
(2x+1)*(4x-9)=0
so, your solution - when one or other multp = 0, so
2x+1=0 and /or 4x-9=0

should be easy to solve it from this point.
Let me know if there is a problem.
Good Luck!

Answer 2

When you factor out the (2x+1) you actually get:
\[(4x ^{2}-9)(2x+1)\] which when further factored get:
(2x+3)(2x-3)(2x+1)
Now you have all three roots.

Answer 3

ok thanks!