k/3 + 4 -2k = -9k
First you add 9k to both sides
k/3 + 4 -2k = -9k
+9k +9k
k/3 + 4 + 7k = 0
Now subtract 4 from both sides
k/3 + 4 + 7k = 0
-4 -4
k/3 + 7k = -4
Now multiply 3 by both sides
k/3 + 7k = -4
x3 x3 x3
k +21k = -12
Now add k + 21k
22k = -12
Now divide both sides by 22
22k = -12
----- -----
22 22
k = -6/11
