Answer:
12
Step-by-step explanation:
Because this is a 45 angle triangle we can assume the other side is also a 45 angle. Which means that CD=AD.

So area of cake
area=pi times radius^2
diameter=2radius
diameter/2=radius
find radius
diameter=6
6/2=raidus=3
formula is
A=3.14 times 3^2
A=3.14 times 9
A=28.26 cm^2
Y = mx + b
slope(m) = 3/4
(3,7)...x = 3 and y = 7
now we sub and find b, the y int
7 = 3/4(3) + b
7 = 9/4 + b
7 - 9/4 = b
28/4 - 9/4 = b
19/4 = b
so ur equation is : y = 3/4x + 19/4
if point A (x,5) lies on the line.....
y = 3/4x + 19/4......when y = 5
5 = 3/4x + 19/4
5 - 19/4 = 3/4x
20/4 - 19/4 = 3/4x
1/4 = 3/4x
(1/4) / (3/4) = x
1/4 * 4/3 = x
4/12 reduces to 1/3 = x......so point A is (1/3,5)...with x being 1/3