The answer is :
c. (x+1)²=20
To check:
(x+1)²=20 (a+b)²=a²+2ab+b²
x²+2x+1=20
x²+2x=20-1
x²+2x=19
Answer:
200
Step-by-step explanation:
So it'll be 400 ÷ 2 = 200 , and a way to to check your way would be 200 x 2 = 400


When

, you're left with

When

or

, you're left with

Adding the two equations together gives

, or

. Subtracting them gives

,

.
Now, you have



By just examining the leading and lagging (first and last) terms that would be obtained by expanding the right side, and matching these with the terms on the left side, you would see that

and

. These alone tell you that you must have

and

.
So the partial fraction decomposition is
275,000 km
The moons A, B, C form a right triangle with AC forming a hypotenuse with the diameter of the planet and the distance of both moons from the surface. So add A to the surface, plus the diameter of the planet, plus surface to c.
115000+45000+115000 = 275000