Question

How do you simplify `15 + 3[(5-1)(7-2)2-4]` using PEMDAS?

Answer 1

`123`

Explanation:

Count the number of terms first. Each term must simplify to a single answer and these are added or subtracted in the LAST step.

Within each term - do parentheses/brackets first, then work from the strongest operations of powers and roots, followed by multiplication and division. Only then are the additions and subtractions done.

`color(magenta)(15) + color(orange)(3xx)[color(red)((5-1)(7-2))color(blue)(xx2)color(lime)(-4)]` has two terms.

=`color(magenta)(15) + color(orange)(3xx)[color(red)((4))xxcolor(red)((5))color(blue)(xx2)color(lime)(-4)]`

=`color(magenta)(15) + color(orange)(3xx)[color(red)(20)color(blue)(xx2)color(lime)(-4)]`

=`color(magenta)(15) + color(orange)(3xx)[color(red)(40)color(lime)(-4)]`

=`color(magenta)(15) + color(orange)(3xx)color(red)(36)`

=`color(magenta)(15) + color(orange)(108)`

=`123`