Question

explain two ways to evaluate 45(13+18)

Answer 1

Step 1

Way number 1

you can do the addition and then, the multiplication, it is

$\begin{gathered} 45(13+18)= \\ 45(31)=45\cdot31 \\ 1395 \end{gathered}$

Way number 1

you can use the distributive property to eliminate the parenthesis, a little reminder

$a(b+c)=ab+ac$

then

$\begin{gathered} 45(13+18)= \\ 45\cdot13+45\cdot18 \\ 585+810 \\ 1395 \end{gathered}$

and the result is the same