Answer:
first answer is correct
Step-by-step explanation:
Hello, we want to write 2 + 4 + 6 + ... + 20
for n = 1, 2n = 2*1 =2
for n = 2, 2n = 2*2=4
for n = 3, 2n=2*3=6
etc
so

thanks
Answer:
I think c 430 and if it is wrong I'm so sorry
The answer is 75° because all three angles of a triangle must add to 180°
Answer:
2/3
Step-by-step explanation:
I am not sure
Answer:
-11/12
Step-by-step explanation:
Add 5/8+3/4 (6/8) which is 11/8 and then get -2/3 - 5/6 which simplifies to -3/2
Multiply -3/2 by 4 to get it to like terms
11/8 / -12/8
Multiply and then simplify.
If you need help, just comment!!