SOLUTION: Solve the following equation by first doing a substitution to make it a quadratic. x^4 - 7x^2 + 10 =0

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Solve the following equation by first doing a substitution to make it a quadratic. x^4 - 7x^2 + 10 =0      Log On


   



Question 1061505: Solve the following equation by first doing a substitution to make it a quadratic.
x^4 - 7x^2 + 10 =0

Found 2 solutions by rothauserc, ikleyn:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
x^4 -7x^2 +10 = 0
:
Let u = x^2, then
:
u^2 -7u +10 = 0
:
(u - 5) * (u - 2) = 0
:
x^2 = 5
:
x = square root (5)
:
x^2 = 2
:
x = square root (2)
:
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There are two solutions
:
x = square root (5)
x = square root (2)
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:

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
Solve the following equation by first doing a substitution to make it a quadratic.
x^4 - 7x^2 + 10 =0
~~~~~~~~~~~~~~~~~~`

There are 4 (four) solutions:

sqrt%285%29, -sqrt%285%29, sqrt%282%29, -sqrt%282%29.



Plot y = x%5E4+-+7x%5E2+%2B+10