Just find the inverse cosine of 1 which is 0 degrees.
Answer:

From this, you can tell it's in slope-intercept form, has a slope of -1/2, and a y-intercept of -4.
I've included a picture of what this equation looks like.
Answer:
B
Step-by-step explanation:
It is not a scalene triangle because a scalene triangle has no sides equal and the triangle shown has 3 equal sides.