Circles Flashcards
1
Q
Perimeter of circle formula:
A
2πr or πd
2
Q
What do you do when it says on your pi question, “… to 2 decimal places”?
A
press π button on calculator
3
Q
What do you do when it says “exact circumference”?
A
Keep π in your answer
4
Q
What do you do if you have to find the perimeter of the arc length?
A
θ/360 x πd
5
Q
How do you find the exact perimeter?
A
You find the arc length first then substitute it into the perimeter formula and times the radius by 2.
6
Q
What is the area of a circle?
A
πr²
7
Q
What is the area of a sector?
A
θ/360 x πr²
