You could rewrite this as double brackets, as you are multiplying together two sets of two terms. It would then look like:
(8i + 6j)(4i + 5j)
and you can expand by multiplying together all of the terms
8i × 4i = 32i²
8i × 5j = 40ij
6j × 4i = 24ij
6j × 5j = 30j²
To get your final answer, you then just need to add together all of the like terms, and get 32i² + 30j² + 64ij
I hope this helps!
