Answer:
x= 12
Step-by-step explanation:
First, we can note that the angles in a pentagon add up to 540°
We can, using the image below, conclude that angles a+b+c+d+f=540
Furthermore, a is on a straight line with 7x+4, and so on, so
180-(7x+4)= a
176-7x=a
180-(4x+1) = b
179-4x = b
180-(9x-6) = c
186 - 9x = c
180 - (4x+9) = d
171 - 4x = d
180 - (5x+4) = f
176 - 5x = f
a+b+c+d+f = 540
176-7x + 179-4x + 186 - 9x + 171 - 4x + 176 - 5x = 540
888 - 29x = 540
348 = 29x
x = 12
