We are asked to find the area of patio. It is circular so formula used for area is given by:

Where
r = radius = diameter / 2 = 20 / 2 = 10 feet

When we round this to the nearest whole number:
3 gallons are in 12 quarts. 4x3=12. 4 qts make 1 gallon
Answer:52
Step-by-step explanation:
Sq rt(169) - 13
13 is the side length
13*4=52
X=-b+-sqrt (b^2-4ac)/2a
x=-11+-sqrt (11^2-4(8)(-300)/16
x=-11+-sqrt (121+9600)/16
x=-11+-sqrt (9721)/16
x=-11+-98.6/16
x=5.48 or x=-6.85