Answer: (no promises this is exactly right)
-2r+6
Step-by-step explanation:
−3r+9+r+−3
=
(−3r+r)+(9+−3)
=
−2r+6
Mean = it's really just another word for average. You add all the values up together, and divide the sum by the number of values there are. So here :
9 + 13 + 9 + 10 + 10 + 9 + 10 + 10 + 11 + 9 = 100
And now, you count how many values there are ^ up there. There are 10 values (just count how many numbers there are) and then you have to divide 100 by 10.
100 ÷ 10 = 10
Your MEAN is : 10
Answer:
135 degrees
Step-by-step explanation:
- Angle CBD is the sum of angle ABC and angle ABD, so we find these first
- An Isosceles triangle has 2 equal sides and 2 equal angles
- Isosceles triangle theorem tells us that the 2 equal angles are respectively opposite the equal sides
- Since triangle ABC has sides AB=AC, then angle ACB = angle ABC
- So knowing that angles of triangle add up to 180, then
- Now we do the next triangle to get ABD
- Since triangle ABD has sides AB=BD, then angle BDA = angle BAD
- So knowing that angles of triangle add up to 180, then
- Now we said, angle CBD is the sum of angle ABC and angle ABD, so

Translating the half to symbols would be 1/2. Therefore, your answer is 1/2(n)
Hope this helps!