SOLUTION: PLEASE HELP ME!!! question: The area of a circle is given by A = pi(4x^2 + 12x + 9. Find the expression for the radius of the circle. H_E_L_P!!!

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Question 76361: PLEASE HELP ME!!!
question: The area of a circle is given by A = pi(4x^2 + 12x + 9. Find the expression for the radius of the circle.
H_E_L_P!!!

Answer by Earlsdon(6294)   (Show Source): You can put this solution on YOUR website!
The area of a circle is given by:

As you probably know,the formula for the area of a circle is:

Set these two equal to each other:
Divide both sides by
Now factor the right-hand side.
Take the square root of both sides.

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