The first two is wrong, the last two is one of the right ones, I think it’s c
Answer:
n = -2
Step-by-step explanation:
4n + 12 = 4
Subtract 12 from both sides.
4n = -8
Divide both sides by 4.
n = -2
You can solve for sides of a triangle using the following equation.
A = arccos (b^2 + c^2 - a^2/2bc)
And likewise for other variables by moving the letters.
Ultimately, in this problem you get the following angle measures:
15.87
23.97
140.16