Math Is Fun Forum

Yes I own a protractor So that makes  Ab= 60 bc= 75

It's an Acute Triangle so all the angles are less then 90.

Abo = 45
Obc = 45
Boc  = 15

And when I add 45+15+30+45+15+30= 180 So that makes it correct.

So my answer would be the arc of AB= 30

But weren't these talking about a central angle  The measure of a central angle is equal to the length of the arc it defines.  and we are talking about an inscribed angle now right ?

#12- I choose 4(D) because the hypotenuse is two times that of the leg opposite the 30 degree angle. The leg opposite the 30 degree angle is 60 degree angle and the question said AB is 4 So, I multiply 4 * 2=8 and the radius = 1/2 * 8 = 4 So that is my answer.

12. If ABC is a 30-60-90 triangle, with angle ACB at 30 degrees, and line segment AC is the diameter of the circle, then if the length of line segment AB is 4, what is the radius of the circle?

A 8
B 2
C 10
D 4
E 7
F 16

#13- I choose A

13. Working with the information from 12 from here to #16, what is the measure of arc AB?
A 90 deg
B 25 deg
C 30 deg
D 120 deg
E 60 deg
F 72 deg

#14- F

14. What is the measure of arc BC?
A 20 deg
B 45 deg
C 75 deg
D 120 deg
E 15 deg
F 90 deg

15- E

15. Are arcs ABC and AC equal?
A maybe
Bnone of these
Ckinda
D55
E yes
F no

I was wondering how I can find that ?

16. What is the measure of chord BC?
A 6.928
B 2.098
C 5.281
D 10.112
E 9.475
F 7.461

I have 10 more left but I am still working on then lol

9 is the length of DJ and it is equal to 3√3 *√3

So the other side is 3√3 and the hypotenuse =  3√3 *2 which gives me 6√3 which is 6*sqrt(3)

I used the Special Right Triangles formula

1 is the radius but the diameter is 2

but AM is 2 and Mi is 2  so isn't AI going to be 2^2+2^2

So 2^2 +2^2= c^2
     4+4= c^2
     c^2=8
   sqrt 8

lol sorry I posted that before reading post #31 Thank you !

ooooh but the radius of the circle is half the diameter So from M to c that is 2