SOLUTION: solve each equation 1) 6x^3-13x^2-5x=) 2) 5(3a-1)^2+3=-16(3a-1)

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Question 65037: solve each equation
1) 6x^3-13x^2-5x=)
2) 5(3a-1)^2+3=-16(3a-1)
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
There was a type-o on 1) so I changed ) to 0 because that made the most logical sense to me.
solve each equation
1) 6x^3-13x^2-5x=0
x%286x%5E2-13x-5%29=0
x%286x%5E2%2B2x-15x-5%29=0
x%28%286x%5E2%2B2x%29%2B%28-15x-5%29%29=0
x%282x%283x%2B1%29-5%283x%2B1%29%29=0
x%282x-5%29%283x%2B1%29=0
x=0 or 2x-5=0 or 3x+1=0
x=0 or 2x=5 or 3x=-1
x=0 or x=5/2 or x=-1/3
:
2) 5(3a-1)^2+3=-16(3a-1)
5%283a-1%29%5E2%2B16%283a-1%29%2B3=0
Let 3a-1=p
5p%5E2%2B16p%2B3=0
5p%5E2%2B15p%2Bp%2B3=0
%285p%5E2%2B15p%29%2B%28p%2B3%29=0
5p%28p%2B3%29%2B1%28p%2B3%29=0
%285p%2B1%29%28p%2B3%29=0
5p+1=0 or p+3=0
5p=-1 or p=-3
p=-1/5 or p=-3
Let p=3a-1
3a-1=-1/5 or 3a-1=-3
3a=1-1/5 or 3a=1-3
3a=4/5 or 3a=-2
(1/3)(3a)=(1/3)(4/5) or 3a/3=-2/3
a=4/15 or a=-2/3
Happy Calculating!!!