Answer:
Answer is 81.
Step-by-step explanation:
Given two expressions are
and 
Now we divide first expression by the second.


Therefore 81 is the answer.
Let's look at each pair and change it so the first one in the pair will be what the second one will be converted to.
8,600 mg = 86,000 mg; So now, the first one is not equivalent.
2,500 g = 250,000 g; Not that one either.
3.4 kg = 3.4 kg; This one is correct. We can check by checking the last pair.
480 g = .0048 g; Nope.
So 3.4 kg, 3400 g would be the correct answer.
120+.5x=50+.7x
Subtract 50 from both sides and then subtract .5x from both sides to get 70=.2x. Then divide both sides by .2 to get x=350.
Answer:
x=8,-9
Step-by-step explanation: