So the question is asking: (x-4)(x-2) because there is a bracket in between the two expressions it means we have to multiply them together: (x-4) x (x-2)
you can break down the question into smaller parts: x multiply x x multiply -2 -4 multiply x -4 multiply -2
here are the answers: x^2 (means x squared) -2x -4x 8 (because when you multiply two negative numbers it makes a positive)
now you put it into an expression (this is expanding): x^2 - 2x - 4x + 8
to simplify it you collect like terms: x^2 - 6x + 8
