Question 44976
1. x^3-x^2-20x=0
x(x^2-x-20)=0
x(x-5)(x+4)=0
x=0 or x=5 or x=-4
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2. 5x^2+3x=2
5x^2+3x-2=0
Use the quadratic formula to get:
x=[-3+sqrt(9-4*5*2)]/10 or x==[-3-sqrt(9-4*5*2)]/10 
x=[-3+2sqrt10]/10 or  x=[-3-2sqrt10]/10
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3. x(x-5)=36
x^2-5x-36=0
(X-9)(X+4)=0
x=9 or x=-4
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This problem is an equation and I have tried to figure out the answer but I'm stuck.
4. 4a^4b+32ab^4
Not an equation as you have posted it.
Cheers,
Stan H.