Question

Question #56e85

Answer 1

Solution: `n= -7.27 (2dp) or n= -10.73(2dp)`

Explanation:

#n^2 +18n +74 = -4 or n^2 +18n = -78 or n^2 +18n +81 = -78+81 or (n+9)^2 =3 or n+9 = +- sqrt3 :. n = -9 +sqrt3 = -9 +1.732 = -7.27 (2dp) or n= -9 -sqrt3 = -9-1.732 = -10.73(2dp)#

Solution: `n= -7.27 (2dp) or n= -10.73(2dp)` [Ans]