Solving for a variable in an equation means, we are changing the subject of formula of the equation.
The equation of r is: 
The equation is given as:

We start by multiplying both sides by 3

Rewrite as:

Divide both sides by 

Cancel out common factors

Take square roots of both sides

Evaluate the right-hand sides

Make r the subject

Hence, the resulting equating for r is:

Read more about the subject of formulas at:
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Answer:
which one?
Step-by-step explanation:
<span>A
and B must be invertible, we have UA=B, since A is invertible. A^-1 exists, by multiplying with A^-1,
we have UA A^-1 =B A^-1. But AA^-1 = I (identity matrix)
and XI=X, for all matrix X, we find UI= B A^-1, and U= B A^-1.</span>
I’m pretty sure the answer is c.
Since each I guess ‘layer, or cubes will have 12 cubes.
The height is 4
12*4=48
I hope this helps, I’m really sorry if the answer is wrong
The real solutions of f(x) = 0 is; x = -8, 0 and 4
<h3>How to find the roots of a polynomial graph?</h3>
When talking about real solutions of a polynomial, we are simply referring to the values of x that make the polynomial f(x) = 0.
Now, in a polynomial graph as attached, the real solutions are the roots and they are the values of x where the curve crosses the x-axis.
From the given graph, the real solutions are at x = -8, 0 and 4
Thus, we conclude that the real solutions of f(x) = 0 is; x = -8, 0 and 4
Read more about Polynomial roots graph at; brainly.com/question/14625910
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