PhysChemTutor's answer to help's Secondary 3 A Maths Singapore question.
where did Q ; -3*3 came from ???
To get the 12 from 4, you have to × 3. That is 3×4 to get 12. But you time 3 to 4, you must × 3 to the other two terms as well. (-X+1)is -3. So -3×3
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