Answer:
r = 16 units
Step-by-step explanation:
From the figure attached,
AB is the tangent drawn from a point A to the circle C.
BC = r [Radius of the circle]
Length of AC = (18 + r)
AB = 30
By the property of a tangent drawn to a circle,
"Radius of a circle and tangent are perpendicular to each other"
AB ⊥ BC
By applying Pythagoras theorem in ΔABC,
AB² + BC² = AC²
(30)² + r² = (r + 18)²
900 + r² = r² + 36r + 324
36r = 900 - 324
r = 
r = 16 units
Answer:

Step-by-step explanation:
Since the fractions are like, their denominators are 11, then
consider the values that sum to give 18 , that is
1 + 9 + ? = 18
10 + ? = 18 ( subtract 10 from both sides )
? = 8
Then the third fraction is 
Answer:
2300
Step-by-step explanation:
Answer:
546 ft³
Step-by-step explanation:
In the figure attached, the top view of the pool is shown. It can be decomposed into a trapezoid which height is 12 ft and which bases are 9 ft and 11 ft; and a rectangle which height is 1.5 ft and and it base is 11 ft.
Area of the trapezoid: (9 + 11)/2 * 12 = 120 ft²
Area of the rectangle: 1.5*11 = 16.5 ft²
Total area: 120 + 16.5 = 136.5 ft²
Volume of the pool: Total area * deep = 136.5 * 4 = 546 ft³