how do you solve m/4+6=3 using the undo method

Question

how do you solve an equation using the undo method?

Answer 1

(m/4)+6=3

(m/4)=-3

m=-12

Answer 2

If you have the Do-Undo sheet in front of you we’ll start with the Do column. The variable is m, so what is done to m? We start at the top of the column.

Do

•÷4

+6

In the Undo column against ÷4 write ×4.

In the Undo column against +6 write -6.

Now we need to apply the Undo. We start at the bottom of the column. Subtract 6 from 3 to give us -3.

Now multiply -3 by 4 and we get -12.

So m=-12.