If I was born in 1996 in 2017 i am 21 years old. From year 1996 to year 2006 there are 10 years. From year 2006 to year 2016 there are 10 years. -> From year 1996 to year 2016 there are 10 + 10= 20 years. And from year 2016 to year 2017 there is 1 year. So, 10+10+1=21 years will pass from 1996 till 2017.
Since y is anything greater than 2, you would draw a straight line across the point (from left to right) and if you had to shade you would shade above it (:
