144. b2 ——- - ——— 5 (12-b). 5 (12-b)
To simplify the expression you provided, I assume it is meant to be presented as follows:
\[ \frac{b^2}{5(12-b)} - \frac{5(12-b)}{5(12-b)} \]
Let's simplify this step-by-step.
The second fraction simplifies to 1 because the numerator and the denominator are the same: \[ \frac{5(12-b)}{5(12-b)} = 1 \]
Therefore, the expression can be rewritten as: \[ \frac{b^2}{5(12-b)} - 1 \]
To combine these terms, we need a common denominator. The common denominator is \(5(12-b)\): \[ \frac{b^2}{5(12-b)} - \frac{5(12-b)}{5(12-b)} = \frac{b^2 - 5(12-b)}{5(12-b)} \]
Now, distribute the \(5\) in the numerator: \[ 5(12-b) = 60 - 5b \]
So, we rewrite the numerator: \[ b^2 - (60 - 5b) = b^2 + 5b - 60 \]
Therefore, the simplified expression is: \[ \frac{b^2 + 5b - 60}{5(12-b)} \]
This is the final simplified form of the expression. If you have more details or context, please provide them for further assistance!
