A+c = 150
10.25a+7.75c = 1470
Answer:
Step-by-step explanation:
The formula for determining the the area of a sector is expressed as
Area of Sector = θ/360 × πr²
Where
θ represents the central angle.
π is a constant whose value is 3.14
r represents the radius of the circle.
From the information given,
The central angle is π/7 radian. Converting to degrees, it becomes
π/7 × 180/π = 180/7 = 25.714 degrees.
Area of sector = 77 square meters
Therefore
77 = 25.714/360 × 3.14 × r²
77 = 0.2243r²
r² = 77/0.2243 = 343.29
r = √343.29 = 18.53 meters
Answer:
2x + 10 = x
Step-by-step explanation:
- -> Robert mows = 2x + 10 yards
- According to the given condition:
- 2x + 10 = x (This is the required expression)
She asked her friends, which does not represent a random sample.
She tried to show cause and effect without doing an experiment (which includes simple random sample, control group, treatment, etc).
So the answer is she did not use a random sample, and tried to show cause and effect with an observational study.