Points A,B and C lie on a circle with center Q.- The area of sector AQB is twice the area of sector BQC.- The length of arc AB is 28 centimeters.What is the length, in centimeters, of arcBC ?
Q. Points A,B and C lie on a circle with center Q.- The area of sector AQB is twice the area of sector BQC.- The length of arc AB is 28 centimeters.What is the length, in centimeters, of arcBC ?
Identify Angle Relationship: Since the area of sector AQB is twice the area of sector BQC, the angle for sector AQB must be twice the angle for sector BQC.
Assign Angle Measures: Let's call the angle for sector BQC x degrees. Then the angle for sector AQB is 2x degrees.
Calculate Total Angle: The total angle for a circle is 360 degrees. So, the sum of the angles for sectors AQB and BQC is 360 degrees.
Set Up Equation: We can write an equation: 2x+x=360.
Solve for Angle: Solving for x gives us x=120 degrees. So, the angle for sector BQC is 120 degrees, and the angle for sector AQB is 240 degrees.
Determine Arc Length: The length of arc AB is 28 centimeters, which corresponds to the angle of 240 degrees.
Find Length of Arc BC: To find the length of arc BC, we need to find what length corresponds to 120 degrees.
Set Up Proportion: We can set up a proportion since the lengths of arcs are proportional to their angles.
Cross-Multiply: The proportion is 240degrees28cm=120degreeslength of arc BC.
Solve for Arc BC: Cross-multiplying gives us (28cm×120∘)=(length of arc BC×240∘).
Calculate Arc BC Length: Solving for the length of arc BC gives us length of arc BC = (240degrees28cm×120degrees).
Calculate Arc BC Length: Solving for the length of arc BC gives us length of arc BC = (28cm×120∘)/240∘. Calculating that gives us length of arc BC = (28×120)/240=3360/240=14 centimeters.
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