Scalene trian<span>gle
-----------------------
</span>
Answer:
an = a(n-1) - 7
Step-by-step explanation:
the second term is smaller than the first term 7.
a20 = a19 - 7
a19 = a18 - 7
=> a20 = (a18 - 7) - 7
Then you can accumalate until a1
-> a20 = a1 - 19*7 = 86 - 19*7 = -47
The two given angles are vertical angles which mean they are the same:
9x + 72 = 4x + 112
Subtract 72 from bot sides:
9x = 4x + 40
Subtract 4x from both sides:
5x = 40
Divide both sides by 5:
X = 8
Answer:
5
Step-by-step explanation: