Question 240936
-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
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Ed