Question 416053
x/2 + y/2 = 9 and 
x+y=18
sqrt of xy = 7.2=7 1/5 = 36/5

xy = 1296/25
y = 1296/25x
plug value of y in the other equation

x+1296/25x=18
25x^2+1296=450x
25x^2-450x+1296=0
Solve using quadratic formula
Discriminant =72900


x=14.4 OR 3.6
y=3.6 OR 14.4