2nd Area of a sector

Front

What is the formula for the area of a sector?

Back

Area = (θ/360) × πr², where θ is the angle in degrees and r is the radius.

Front

How do you convert degrees to radians?

Back

Multiply degrees by π/180.

Front

What is the relationship between the radius and the area of a sector?

Back

The area of a sector increases with the square of the radius.

Front

If the radius of a sector is doubled, how does the area change?

Back

The area increases by a factor of four.

Front

What is the area of a sector with a radius of 5 cm and an angle of 60 degrees?

Back

Area = (60/360) × π × (5)² = 13.09 cm² (rounded to 2 decimal places).

Front

How do you round a number to one decimal place?

Back

Look at the second decimal place; if it's 5 or more, round up the first decimal place.

Front

What is the area of a sector with a radius of 7 cm and an angle of 90 degrees?

Back

Area = (90/360) × π × (7)² = 38.48 cm² (rounded to 2 decimal places).

Front

What is the area of a sector with a radius of 10 cm and an angle of 45 degrees?

Back

Area = (45/360) × π × (10)² = 17.45 cm² (rounded to 2 decimal places).

Front

What is the significance of π in the area of a sector formula?

Back

π (pi) is a constant that represents the ratio of the circumference of a circle to its diameter.

Front

How do you find the area of a sector if the angle is given in radians?

Back

Area = (1/2) × r² × θ, where θ is in radians.