Posted by Emmett on .
Find all real solutions of the equation by first rewriting the equation as a quadratic equation. (Enter your answers as a commaseparated list.)
4x4 + 15x2 − 4 = 0

MATH 
MathMate,
Let y=x²
the equation can then be written as
4y²+15y4=0
Solve for y using the quadratic formula (i.e. find y1 and y2).
Since y=x², then
x=±√(y1) or ±√(y2)
giving a total of 4 solutions.