Its true for integers if you are using the associative property in addition or multiplication ONLY.
Answer:
the Slope is 
Step-by-step explanation:
Answer:
x = 20
Step-by-step explanation:
angle 2 and 3 are congruent, becaus they are alternate interior angles. So, 3x-10 = x+30, 2x = 40, x= 20.
The answer would be 1:4 because when you divide 2:8 by 2 you get 1:4