Answer:
x= 45
Step-by-step explanation:
x= -15*-3
x= 45
(0,-6), (6, -3), and (6,-6)
If you plot them on a graph there are only two point options (in green and purple) since it's a right triangle but you have to use the one that has -6 as the y value
Are a and b two points on a line
If they are you can use the distance formula
Answer: 
Step-by-step explanation:
If you meant to solve for "z", then refer to the attachment below.
X= 100°
180° - 57° = 123
x + 23°= 123°
x = 100°