b) \( \square \cdot-15=-90 \)

To solve the equation \( \square \cdot -15 = -90 \), start by isolating the square. You can do this by dividing both sides of the equation by -15 to eliminate the multiplication: \[ \square = \frac{-90}{-15} \] This simplifies to \( \square = 6 \). So, the value that fits in the square is 6! Here's a fun fact: the number -15 is a multiple of 3, which means when you divide -90 by -15, you're not just getting the solution directly; you're also practicing your multiplication tables along the way! Mathematically pleasing, right? Also, keep in mind when working with variables that negative signs can cause confusion! A handy tip: always pay attention to the signs in your multiplication or division. It's a common mistake to overlook them, which can throw your final answer off by flipping its sign. Stay sharp and review those signs!