Here, You need to understand "The Linear Pair" equation, it tells, one straight line gives 180 degrees of angle (number of different angle doesn't matter)
Now, by applying this, we can get all the angles of that Pentagon:
180 - 60 = 120
180 - 70 = 110
180 - 65 = 115
180 - 40 = 140
180 - y = 180 - y
Now, Sum of all the angles would be 540,
120 + 110 + 115 + 140 + 180 - y = 540
665 - y = 540
y = 665 - 540
y = 125
In short, Your Final Answer would be 125
Hope this helps!