Answer:
Step-by-step explanation:
Two numbers r and s sum up to \frac{1}{2} exactly when the average of the two numbers is \frac{1}{2}*\frac{1}{2} = \frac{1}{4}. You can also see that the midpoint of r and s corresponds to the axis of symmetry of the parabola represented by the quadratic equation y=x^2+Bx+C.
D) 30
A polygon can rotate a total of 360. This one has 12 sides and 12 angles that are all congruent. So to coincide with original image, it must rotate 1/12 of the way around
360/12=30
Answer:

Step-by-step explanation:
So we have the equation:

And we want to solve for R.
First, let's multiply both sides by J to remove the fraction on the right. So:

Simplify the right:

We can rewrite our equation as:

So, to isolate the R variable, divide both sides by I²t:

The right side cancels, so:

And we are done!