To evaluate 45(13 + 18), we can use any of these methods.
Method 1
We simplify the expression in the bracket first.
[tex]\begin{gathered} 45(13+18)=45(31) \\ =45\times31 \\ =1395 \end{gathered}[/tex]Method 2
We apply the distributive property.
[tex]\begin{gathered} 45(13+18)=45(13)+45(18) \\ =45\times13+45\times18 \\ =585+810 \\ =1395 \end{gathered}[/tex]