Plane acb
plane bac
plane bca
plane cab
plane cba
Well combine:
2x + 3x + x + 60 = 180
combine like terms:
6x + 60 =180
then move the 60:
6x = -120
now divide both sides by 6:
x= -20
i hope this helped! :)
Answer:
7.1
Step-by-step explanation:
- Find mean
- For each number you subtract the mean and square the result.
- Work out the mean of those squared differences and find square root of that.
- Hope that helped! Let me know if you need further explanation.