Hello!
Judging on the questions you have provided I have come to the conclusion that to solve all of these you need to find the value of x by isolating it all on one side and simplifying.
For question #1 the first step would be to subtract 6 from each side.
The outcome should be -x=-6-12, and if simplified -x=-18.
Next, you want to divide each side by -1 because x needs to always be positive when finding the solution.
Your answer for #1 should be X=18, D.
For question #2 the first step you should take is to subtract 1.33 from each side to isolate x.
The outcome should be x=7.82-1.33, and if simplified x=6.49.
Thus your answer for #2 should be X=6.49, A.
For question #3 the first step you should take to approaching the equation is to isolate x by adding 15.99 towards each side of the equation.
The outcome should be x=58.06+15.99, and if simplified x=74.05.
Thus your answer for question #3 should be X=74.05, D.
Lastly, for question #4 the first step you should take towards isolating x is to divide the entire equation by 1.32.
Your outcome should be x= 6.8
Thus, your answer for the last question, #4, should be X=6.8, C.
Hope this helped!
-Blake
Answer:
Radius = 5 units
Step-by-step explanation:
Diameter of a circle = 10
Radius = diameter/2
Radius = 10/2
Radius = 5 units
The answer is 3/5.

Continue this pattern and you'll see that it follows this geometric sequence
first one: 1200/1.5 = 800, second one: 20,000/10= 2000, third one: 400/20 = 20, fourth one: 266.6, fifth one: 33.3, sixth one: 1000. You're welcome!!