This question is not in any of the formats we have above. So we just need to multiply out the brackets, term-by-term.

It's important to recognize when we have a Special Product and when our question is something else.

(8x y)(3x + 4y)

= 8x(3x + 4y) − y(3x + 4y)

= 8x(3x) + 8x(4y) − y(3x) − y(4y)

= 24x2 + 32xy −3xy − 4y2

= 24x2 + 29xy − 4y2

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