SOLUTION: Please help me solve the equation: {{{ (3f-1)^2+15f=5 }}}.

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Question 269830: Please help me solve the equation: +%283f-1%29%5E2%2B15f=5+.
Found 2 solutions by Alan3354, drk:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Please help me solve the equation: +%283f-1%29%5E2%2B15f=5+.
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You can expand it, but there's quicker way:
+%283f-1%29%5E2%2B15f=5+
+%283f-1%29%5E2%2B15f-5+=+0
+%283f-1%29%5E2%2B+5%2A%283f-1%29+=+0+
((3f-1) + 5)*(3f-1) = 0
(3f+4)*(3f-1) = 0
f = -4/3
f = 1/3

Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
step 1 - expand to get
9f%5E2+-6f+%2B+1+%2B+15f+=+5
combine like terms to get
9f%5E2+%2B+9f+%2B+1+=+5
set = 0 to get
9f%5E2+%2B+9f+-+4+=+0
factoring we get
%283f-1%29%283f%2B4%29+=+0
solving for f, we get
f = 1/3
or
f = -4/3