Question

What is the student error if a student rewrote `4(9x + 10)` as `36x + 10` ?

Answer 1

`36x +40`

Explanation:

The student did not apply the distributive law correctly.

The `4` in front of the bracket must be multiplied by both terms inside the bracket, not just the first as has been been done.

`4(9x+10)`

`= 4xx9x" " +" "4xx10`

`=36x +40`

These are now unlike terms ans cannot be added.
The expressions is now simplified.