Circle Formula Drills Circle Drill Practice Im going

Circle Formula Drills!!!!!

Circle Drill & Practice • I’m going to ask you to remember some formula. • When you think you know the answer, • (or if you give up ) click to get to the next slide to see if you were correct.

Ready?

What’s the definition of a radian?

The ratio of the arc length to the radius!

What’s the m A? arc

Got it? ?

Find x x a c d Notice this picture looks like the last one but now things are written on the Line segments instead of the arcs and angle!

What’s the m arc 1? arc

Remember the chords look like a plus sign!

Find c x a c d Notice this picture looks like the last one but now things are written on the Line segments instead of the arcs and angle!

Moving on…

How do you find area of a circle? ? • What’s your answer?

A=πr 2 • Were you right?

What about the area of a sector?

How are you doing? See how this part is the same formula as area of a circle? ? ?

If you have a central angle, what is true about the measure of the angle and the arc?

They are CONGRUENT!

Where is an INSCRIBED angle and what is the formula to find its measure? ?

ON the circle!! • angle = arc/2

How do you find circumference and what are other words for circumference? ?

C=2πr or πd Perimeter Distance

What about arc length?

How are you doing? See how this part is the same formula as circumference of a circle? ? ?

How are radius and diameter related? • What is your answer?

Diameter = 2 x radius!! • Were you right? (click for next question)

Name all the parts of the circle:

Arc t n a Sec i d a R s u Diamet e r Ch or d n a T t n ge

If angles make the same arc, they are ______ • What is your answer?

CONGRUENT!!! • Were you right? I dig this circle stuff!!

What is the pythagorean theorem? When do you use it? Which side is c? Where is side c? • That’s a lot of questions on one slide!!

• Use it when you have a right triangle • C is the hypotenuse • It is the one across from the right angle!

How many degrees in half a circle? • What’s your answer?

180 o • Remember to look for a diameter (through the center!)

What do you know about vertical angles? • Answer it baby!!

They are CONGRUENT! • Were you right? (click for next question)

If 2 parts of a circle are congruent, what do you know about all the other corresponding parts?

They are CONGRUENT! • Haven’t we had that same answer before? ? ? • Were you right? Remember the pictures for this can look many different ways

• ! What do you know about the lengths of 2 tangents from a common point?

They are congruent!! • There’s that answer again!! • Are you getting tired? We are almost done!!

How many degrees in a whole circle? ? • Get ‘er done!!!

360 o

What is the difference between the MEASURE of an arc and the LENGTH of an arc? • Ready?

Measure is in degrees, length is in distance units like feet or inches or meters

• Only 2 more questions!!! • Go go go go!!!!!

What formula do you use to solve this problem? ?

The Pythagorean Theorem! • Were you right? Remember 8 would be the hypotenuse ©

Find x (formula only) • Oh yeah! Last one baby!

OW = OW • Did ya get it? ? ?

Are you ready? ? Do you know the formulas? ? Run this power point again if you are not 100% certain you have mastered them!

Goodbye!