The answer is 2
Add like terms
Add 8 to -8 and the zero
To get 4x=8
Then divide 4 and 8 by 4
To get x=2
Answer:
26
Step-by-step explanation:
Since x = -5, we can replace x with it's numerical -5, right? The problem tells you that x is equal to -5. So, just replace any x you see with -5.
So in this case,

turns into:

You can use a calculator or solve it by hand to see what the answer is.

For the circumference, you actually multiply by 20 because of the formula πd = C [OR 2πr = C]. You meant to double the radius.
The equation for surface area of a sphere is SA=4*pi*r^2
We can plug in what we know to solve for r
400=4*pi*r^2
100=pi*r^2 (divide out the 4)
100/pi=r^2 (divide out the pi)
√(100/pi)=r (square root of both sides)
r=5.6 rounded to the nearest tenth
The answer is D 5.48*10-8
hope this helps