When the sum of 396 and four times a positive number is subtracted from the square of the number, the result is 84. Find the number.
What I did:
From here I am stuck, when I put it into the quadratic formula it gives me a negative and we aren't allowed to use imaginary numbers. I'm lost.
Here is the next problem:
A man built a walk of uniform width around a rectangular pool. If the area of the walk is square feet and the dimensions of the pool are feet by feet, how wide is the walk?
another negative in the quadratic equation...
Any help would be greatly appreciated!