we have

Using a graph tool------> to resolve the second order equation
the solution is

so

therefore
the answer is the option
length = (x + 18) inches and width = (x + 9) inches
The perimeter of the semicircle would be 25.7 cm
Answer : 4.5 × 10⁴ square inches can be washed per hour.
Step-by-step explanation :
As we are given that an area can be washed at a rate of 4,900 cm²/min. Now we have to determine the square inches can be washed per hour.
Given conversions are:
1 cm = 0.39 in and 1 hr = 60 min
As, 1 cm² = (0.39)² in² and 1 min = 1/60 hr
So, 

Now we have to determine the square inches can be washed per hour.
As, 
So, 
Therefore, 4.5 × 10⁴ square inches can be washed per hour.
Answer:
the answer is DBC=90°
because the midpoint of the perimeter of quadrilateral is B