'cover up' method

it seems helpful to begin work on solving equations informally - just by thinking about them

equations involving trickier 'take away from' and 'divide into' operations, lend themselves to being solved by staging or simplifying a given equation - sometimes this is called the 'cover up' or sometimes the 'big hand' method

you can use your hand to cover up a part of the expression (the cloud in the examples below)

some students prefer this technique to one involving inverse operations
maybe unfortunately...
maybe sensibly...