SOLUTION: How do you solve the following quadratic equations: -6(u+5)^2=120 3s^2-1=7s^2

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Question 240936: How do you solve the following quadratic equations:
-6(u+5)^2=120

3s^2-1=7s^2
Found 2 solutions by stanbon, edjones:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve the following quadratic equations:
-6(u+5)^2=120
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(u+5)^2 = -20
u+5 = 2isqrt(5) or -2isqrt(5)
u = -5+2isqrt(5) or u = -5-2isqrt(5)
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3s^2-1=7s^2
4s^2 = -1
s^2 = -1/4
s = i/2 or s = -i/2
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Cheers,
Stan H.

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
-6(u+5)^2=120
(u+5)^2=-20
u^2+10u+25=-20
u^2+10u+45=0
u^2+10u =-45
u^2+10u+25=-45+25 Completing the square
(u+5)^2=-20
u+5=+-sqrt(-20) Take sqrt of each side.
u=-5+-2sqrt(-5)
u=-5+2sqrt(5)i, u=-5-2sqrt(5)i
.
Ed