Answer:
Hello,
I have reply too quick in comments (sorry)
Step-by-step explanation:

Answer:
All sides are the same length (congruent) and all interior angles are the same size (congruent). To find the measure of the angles, we know that the sum of all the angles is 1260 degrees (from above)... And there are nine angles... So, the measure of the angle of a regular nonagon is 140 degrees.
Step-by-step explanation:
Step-by-step explanation:
6k + 12 + 9=9
6k + 12 = 9 - 9
6k + 12 = 0
12 = -6k
12/-6 = -6k/-6
2/-1 = k
k = -2
X = 26 because all the angles in a triangle add up to 180.
Answer:
x = 39.1
Step-by-step explanation:
To find the mean, add up all the data points and then divide by the number of data points
(31.7+ 42.8+ 26.4+ x)/4 = 35
Multiply each side by 4
(31.7+ 42.8+ 26.4+ x)/4*4 = 35*4
(31.7+ 42.8+ 26.4+ x) = 140
Combine like terms
100.9+x = 140
Subtract 100.9 from each side
x = 140-100.9
x = 39.1