It is none of them. The answer should be -8.
Explanation:
(2 times -8 - 12) = -28
(-16 - 12) = -28
(-28) = -28
-28 = -28
Answer:
<h2>x = -4 or x = 7</h2>
Step-by-step explanation:

The summation of negative 5 n minus 1, from n equals 3 to 12 can be
expressed as
n = 3/12
substitute the value of n to the equatio
-5n – 1
-5( 3/12 ) -1
-9/4
The question said that it told you the base angles. A roof would have two equal base angles. The base angles= 53
All the angles of a triangle each 180, (the roof is shaped like a triangle)
So, let's make x the missing angle.
53(2)+x=180
106+x=180
Subtract 106 on both sides.
180-106= 74
The vertex angle is 74.
I hope this helps!
~cupcake