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1. misty1212

HI!!

2. misty1212

you have a cubic equation to solve?

3. anonymous

yes can you please explain all the steps for me

4. misty1212

there is a formula for solving cubes, but it is almost incomprehensible start with $3x^3+4x^2-27x-36=0$ and then make an educated guess , which is really all you ca ndo

5. misty1212

i guess 3, since 1 and -1 do not work shall we try it?

6. anonymous

ok

7. misty1212

i;ll be damned, it works!

8. misty1212

got it in the first try so this is $(x-3)(\text{ some quadratic})$which you can find using synthetic division or long division (ugh) or thinking (or cheating)

9. misty1212

i can't write synthetic division here, but i can cheat or think you pick

10. anonymous

idk

11. misty1212
12. anonymous

tnx

13. JohnN.

Let's solve your equation step-by-step. 3x3+4x2=27x+36 Step 1: Subtract 27x+36 from both sides. 3x3+4x2−(27x+36)=27x+36−(27x+36) 3x3+4x2−27x−36=0 Step 2: Factor left side of equation. (x+3)(x−3)(3x+4)=0 Step 3: Set factors equal to 0. x+3=0 or x−3=0 or 3x+4=0 x=−3 or x=3 or x=−43 Answer: x=−3 or x=3 or x=−43