Answer:
Step-by-step explanation:
A to C
y = b + mx
b = y-intercept
m = slope of line
Looking at the line, the line crosses the y-axis at the coordinates (0,0). This means that the y-intercept is 0.
The slope formula is m=(y2-y1)/(x2-x1). Using the points on the line (-1, -3) and (1,3) we find that the slope is, 3.
Looking back we can see that our variables now have value so we can plug them into our formula.
y = b + mx
b = 0
m = 3
Substitute
y = 0 + 3x
2. Angle Addition Postulate as they are adding both angles
3. 60 + 40 = m <ABC because it's a substitution
4. 100 = m <ABC as it is simplified already
5. Definition of obtuse angle
