Answer:
x - 6
Step-by-step explanation:
I'm showing you how I solved it in the picture that I have included.
Answer:
Formula for gravitational force F = G M1 * M2 / R^2 where G is the gravitational constant
F2 / F1 = (R1 / R2)^2 = 1/2 where F2 is the required force
R2 = (2)^1/2 R1 distance for R2 to be 1/2 force at R1
Since force is proportional to the square of the distance of separation, increasing the distance of separation by 2^2 will halve the force
The answer is

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Before we rationalize the denominator, we must simplify the numerator and denominator. We evaluate the square root on the top, and combine like terms on the bottom:

To rationalize the denominator, we multiply by the conjugate. The conjugate is found by making the imaginary term of the complex number, the i part, the opposite sign. The conjugate of -2-i is -2+i:
To convert to percent from fraction you divide the numerator by the denominator. from percent to decimal you move two decimal places to the left.
1. C
2.A
Hope this helps, good luck :D