To solve the equation \( 5(5s - 15) = 9s + 9 \), we start by distributing the 5 on the left side of the equation.
- Distribute the 5: \[ 5(5s - 15) = 5 \cdot 5s - 5 \cdot 15 = 25s - 75 \]
So the equation now looks like: \[ 25s - 75 = 9s + 9 \]
- Next, we want to isolate \( s \) on one side. Start by moving the \( 9s \) from the right side to the left side. To do this, subtract \( 9s \) from both sides: \[ 25s - 9s - 75 = 9 \]
This simplifies to: \[ 16s - 75 = 9 \]
- Now, add \( 75 \) to both sides to isolate the term with \( s \): \[ 16s = 9 + 75 \]
Which simplifies to: \[ 16s = 84 \]
- Finally, divide both sides by \( 16 \) to solve for \( s \): \[ s = \frac{84}{16} \]
This can be simplified: \[ s = \frac{21}{4} \quad \text{or} \quad s = 5.25 \]
Thus, the solution to the equation is: \[ s = \frac{21}{4} \text{ or } s = 5.25 \]