Last angle is 122 if its a triangle
B involves direct variation.
y and x are directly proportional.
Answer:
the slope-intercept equation of a line that passes through the coordinate (-4,5) and (8,-1) is

Step-by-step explanation:
1) Apply the slope formula; y^2 - y^1 divided by x^2 - x^1
y^2 is -1
y^1 is 5
x^2 is 8
x^1 is -4
-1 - 5 = -6
8 - (-4) = 12
-6/12 is -1/2 or -0.5
2) To find the y-intercept, hoose either of the coordinates and replace y, m, and x in the y= mx+b formula.
5= -0.5(-4) + b
5= 2 + b
3= b
Slope of AB=(2-3)/(1+1)=-1/2; AC=(-1-3)/(-3+1)=-4/-2=2; BC=(-1-2)/(-3-1)=-3/-4=3/4.
The product of two sides that are perpendicular is -1. Slopes of AB and AC are perpendicular so angle A is a right angle. ABC is a right-angled triangle.