Prove: ⁡⁡(-1⁡-⁡4i)⁡(-7⁡-⁡3i)⁡ = -5⁡ + ⁡31i

Complex Numbers: Multiplication of two complex numbers. To prove (-1-4i)(-7-3i) = -5 + 31i, start with the left-hand side members of the given equation. Simply follow the steps on how to expand the product of two binomials. Simplify until the right-hand side members of the given equation are obtained.

Take note, imaginary number i = √(-1) or (i^2) = -1.

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