Question

When an expression is subtracted from (10m + 3n), the result is (-m - 5n). Find the expression, giving your answer in its simplest form.​

Answer 1

9m-2n

The equation would be (9m -2n) - (10m+3n)
But when you subtract a polynomial you do the rule KEEP CHANGE CHANGE
The first equation is the same: 9m-2n
The symbol changes:+
Then the whole last equation changes: -10m-3n
So when you put that together it equals (9m-2)+(-10m-3n)=(-m-5n)