-1/2(2n+4) + 6 = -9 + 4(2n+1)
First thing you must do is distribute to the parentheses.
(-1/2*2n) + (-1/2*4) + 6 = -9 + (4*2n) + (4*1)
-1n - 2 + 6 = -9 + 8n + 4
Now combine like terms.
-n + 4 = 8n - 5
Subtract 4 from both sides.
-n = 8n - 9
Subtract 8n from both sides.
-9n = -9
Divide both sides by -9.
n = 1
The value of n is 1.