## luisz Group Title If the area of a circle whose diameter is pi, is written as a times pi to the b power, what is the value of ab? one year ago one year ago

1. luisz Group Title

no more drawings this time

2. luisz Group Title

I got pi cubed/4

3. Algebraic! Group Title

yep

4. luisz Group Title

so how could I rewrite this?

5. Algebraic! Group Title

rewrite what?

6. luisz Group Title

pi cubed/4

7. luisz Group Title

I need to rewrite as a times pi to the b power

8. micahwood50 Group Title

So, the area is π³/4. Rewrite it as π³/4 = aπ^b. Find the a and b.

9. Mr.Math Group Title

You know the area of a circle is $$\pi r^2$$, where $$r$$ is the radius of the circle. In this case we have $$r=\frac{\pi}{2}$$. Thus the area, call it $$A$$, is $$A=\pi(\frac{\pi}{2})^2=\frac{1}{4}\pi^3.$$ Now if we set this $$A=a\pi^b=\frac{1}{4}\pi^3.$$ Then we have $$a=\frac{1}{4}$$ and $$b=3$$. So $$ab=\frac{3}{4}$$.

10. luisz Group Title

ok

11. micahwood50 Group Title

You asked me why a should be 1/4, not 4. It's because 4 is in denominator, so it is 1/4. π³/4 = (1/4)π³