SOLUTION: 36x^4 - 85x^2 + 49 = 0

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Question 314663: 36x^4 - 85x^2 + 49 = 0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let u=x%5E2, then u%5E2=x%5E4,
36x%5E4+-+85x%5E2+%2B+49+=+0+
36u%5E2-85u%2B49=0
You can factor,
%2836u-49%29%28u-1%29=0
Two "u" solutions:
36u-49=0%0D%0A%7B%7B%7B36u=49
u=49%2F36
x%5E2=49%2F36
x=0+%2B-+7%2F6
.
.
.
u-1=0
u=1
x%5E2=1
x=0+%2B-+1
You then have 4 "x" solutions.