Answer:
Step-by-step explanation:
x+5+x+7x-5=180 degree (being the interior angles of a triangle)
9x=180
x=180/9
x=20 degree
I think it’s the second one but I’m not 100%
Answer:
The 39th triangle number is 780
It is the first option- 12 times one fourth the quotient of 6 and 2
Answer:
=45 b/c all we have to do is subtract the higher number to the lowest number.
