wait read the question properly :::::::::

 

"  find the area included between the curves y^2 =  4ax and x^2 + y^2 = 8x
which lies above the x axis.  "

the area which you have shaded in your post is 

that is the larger region  is

" area included between  y²=4ax and x² + y² = 8x  and x-axis "

 

the area which i have mentioned is the smaller region.......

"area included between y²=4ax and x² + y² = 8x  (only) ......... and lying above the x-axis......."

 

understood????

for reference :

this sum is in RD SHARMA  page number 21.37 problem 48 ........

the answer is 4pi - 32/3 .....