Answer:
you have to have a value for B and D
Step-by-step explanation:
It'd be easier to do #18 if y ou were to break it up:
14* (first term + 14th term)
Sum from n=1 to 14 of n = S = ---------------------------------
14 2
14(1+14)
= ---------------- = 7(15) = 105
2
The sum of twice that is 210. The sum of "1 from n=1 to n=14" is just 14.
The final sum is 210 + 14 = 224 (answer)
Answer:
15.
Step-by-step explanation:
8x - 10 = 110 (vertical angles are equal in measure).
8x - 10+ 10 = 110 + 10
8x = 120
x = 120 /8
x = 15.