If $a * b = 2a + 3b$ for all $a$ and $b$, then what is the value of $4 * 3$?
To find the value of $4 * 3$, I need to apply that formula with $a = 4$ and $b = 3$. That means I have to calculate $2a + 3b$, where $a = 4$ and $b = 3$. This is a simple arithmetic problem: $2a + 3b = 2 \times 4 + 3 \times 3 = 8 + 9 = 17$. Therefore, $4 * 3 = 17$. 