Answer:
50
Step-by-step explanation:
x = √30² - 18² = √576 = 24
tan A = 18/24 = 3/4
∠A = ∠B
tan B = tan A = 24 / y = 3 / 4
y = (24 x 4) / 3 = 32
Z = y + 18 = 32 + 18 = 50
52 weeks
365 days
7days a week
91 days divided by 7 equals
13 weeks
The formula of an area of a circle:

We have
r = 1.8 m
π ≈ 3.14
Substitute:

Part A: After 9 days the radius of algae was approximately 12.81 mm. The reasonable domain to point is (0,9).
Part B: The 9 on the y-intercept represents the amount of algae the experiment started with.
Part C: (12.81-10.12)/7=0.38
5x + 2y = 7....multiply by -3
-2x + 6y = 9
----------------
-15x - 6y = -21 (result of multiplying by -3)
-2x + 6y = 9
---------------add
-17x = - 12
x = 12/17 or 0.7
5x + 2y = 7
5(12/17) + 2y = 7
60/17 + 2y = 7
2y = 7 - 60/17
2y = 119/17 - 60/17
2y = 59/17
y = 59/17 * 1/2
y = 59/34 or 1.7 when rounded <====