SOLUTION: Find all zeros of the trinomial. k(x)=6x^2+x-40 A. x=-5/2 or 8/3. B. x=-5/3 or x=8/2. C. x=5/3 or x=-4. D. x=5/2 or x=-8/3. help please thanks.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons -> SOLUTION: Find all zeros of the trinomial. k(x)=6x^2+x-40 A. x=-5/2 or 8/3. B. x=-5/3 or x=8/2. C. x=5/3 or x=-4. D. x=5/2 or x=-8/3. help please thanks.       Log On


   

Question 998465: Find all zeros of the trinomial. k(x)=6x^2+x-40
A. x=-5/2 or 8/3.
B. x=-5/3 or x=8/2.
C. x=5/3 or x=-4.
D. x=5/2 or x=-8/3.
help please thanks.
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
k%28x%29=6x%5E2%2Bx-40.....factor completely; write x as 16x-15x
k%28x%29=6x%5E2%2B16x-15x-40......group
k%28x%29=%286x%5E2%2B16x%29-%2815x%2B40%29
k%28x%29=2x%283x%2B8%29-5%283x%2B8%29
k%28x%29=%282x-5%29%283x%2B8%29
roots:
if 0=%282x-5%29=>2x=5=>x=5%2F2
if 0=0%283x%2B8%29=>3x=-8=>x=-8%2F3
so, your answer is
D. x=5%2F2 or x=-8%2F3