Common errors in algebra 1

Error 1

Question:
Harun has $m. He spends $5 . How much does Harun have left? Give your answer in terms of m.

Correct answer:
$m-$5 = $(m-5)
Harun has $(m-5) left.

Wrong answer:
Harun has $m - $5 left.

Explanation:
Technically, although $m - $5 is equal to $(m-5), $m - $5 is not simplified.
For example, we do not write "I have $7-$5 left". Instead, we say "I have $2 left".
The unit of measurement should only appear once.

Error 2

Some pupils still wrote j x 7 = j7.

Explanation:
In algebra, we always write the number before the letter.

Overall comments for Practice 1:
Most pupils did the assignment neatly and well. A number of you scored full marks. Well done!

Those who did not score full marks made careless mistakes or did not follow my instructions regarding the brackets and units of measurement. Do try to minimise that!