solution using distributive property -25 * -31

The given expression is $\left(-25\right)\times \left(-31\right)$. = $25\times 31$
We can split 31 as (30 + 1) in two groups.
Now according to the distributive property, multiply a number by a group of numbers added together, so we have;
$$\begin{gathered} 25\times 31 \\ = 25\left(30+1\right) \\ = 25\times 30+25\times 1 \\ = 750+25 \\ = 775 \end{gathered}$$