Answer:-18
Step-by-step explanation:x in (-oo:+oo)
(1/2)*x = -9 // + 9
(1/2)*x+9 = 0
1/2*x+9 = 0 // - 9
1/2*x = -9 // : 1/2
x = -9/1/2
x = -18
brainliest please