9x^2 -c =d
add c to each side
9x^2 = c+d
divide by 9
x^2=(c+d)/9
take the square root on each side
x = +- sqrt ((c+d)/9)
simplify
x = +- 1/3 sqrt (c+d)
Answer: 1/3 sqrt (c+d), - 1/3 sqrt (c+d)
You could move the decimal to the right 6 times
0.2 x 10^6
0200000 or 200,000(remember that if there's only two digits there will be one less zero than the exponent)
Answer: x=4
Step-by-step explanation:
-8-x=x-4x
-8-x=-3x
-8=-2x
x=4
Answer:
If it's not too late by now, the answer is 19.9 
Answer:
320 milligrams of sodium
Step-by-step explanation:
Create a proportion where x is the milligrams of sodium a 20 ounce bottle has:
= 
Cross multiply and solve for x
1920 = 6x
320 = x
So, a 20 ounce bottle will have 320 milligrams of sodium