SOLUTION: solve each equation below by making the appropriate substitution. Be sure to check answer(s): PLEASE HELP ME! A)X^-2+X^-1-56=0 U= u^2= Answer: B)x^2/3-x^1/3-12

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: solve each equation below by making the appropriate substitution. Be sure to check answer(s): PLEASE HELP ME! A)X^-2+X^-1-56=0 U= u^2= Answer: B)x^2/3-x^1/3-12      Log On


   

Question 87938: solve each equation below by making the appropriate substitution. Be sure to check answer(s): PLEASE HELP ME!
A)X^-2+X^-1-56=0
U=
u^2=
Answer:
B)x^2/3-x^1/3-12=0
U=
U^2=
Answer:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A)X^-2+X^-1-56=0
U=x^-1
u^2=x^-2
Answer:u^2+u-56 = 0
(u+8)(u-7)=0
u=-8 or u=7
x^-1=-8 or x^-1=7
x=-1/8 or x=1/7
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B)x^2/3-x^1/3-12=0
U= x^(1/3)
U^2=x^(2/3)
Answer:u^2+u-12=0
(u+4)(u-3)=0
u=-4 or u=3
x^(1/3)=-4 or x^(1/3)=3
x = -64 or x=27
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Cheers,
Stan H.