Step-by-step explanation:
In an equilateral triangle, all the three sides are equal as well as all the angles are equal. Let the angles be x.
We know that the sum of angles of a triangle is equal to 180 degrees. It means that,
x+x+x=180
3x=180
x=60°
Hence, if a triangle is an equilateral triangle, then the triangle has exactly three 60° angles. Hence, △ABC is an equilateral triangle
You can think of this question like the photo attached above.
Hi!
I think for b, the answer would be:
You can construct an angle that is one fourth the measure of angle JKL, by dividing angle either angle MKL or JKM in half.
This is because one-fourth is also equal to one quarter (1/4). If you split angle JKL into 4 equal angles, you would have an angle that is one-fourth the measure (original angle) of angle JKL.
I think for c, the answer would be:
You can construct a 15 degree angle from a given 60 degree angle, by dividing the 60 degree angle into 4 equal angles.
This would work, because each of the 4 angles would be 15 degrees.
Hope this helps! Best of luck!
10% of 13 is 1.3 so 13+1.3= 14.3
Answer:

Step-by-step explanation:
x is the center of the circle.
the chord of length 12 can be splitted into two parts of 6 length each.
since the radius does not change when it touches another end of the circle, we can safely calculate our radius to be the hypotenuse of the triangle formed by the length of the chord and 3.
The explanation is given in the picture