Answer:
x = -7 ±3i
Explanation:
(x+7)^2+9=0
Subtract 9 from each side
(x+7)^2+9-9=0-9
(x+7)^2=-9
Take the square root of each side
sqrt((x+7)^2) = ±sqrt(-9)
We know sqrt(ab) = sqrt(a) sqrt(b)
x+7 = ±sqrt(-1) sqrt(9)
We know that sqrt(-1) is the imaginary number i
x+7 = ±i *3
x+7 =±3i
Subtract 7 from each side
x+7-7 = -7 ±3i
x = -7 ±3i