How do you perform the operation and write the result in standard form given #-8i(9+4i)#? Precalculus Complex Numbers in Trigonometric Form Multiplication of Complex Numbers 1 Answer Kalyanam S. Jul 11, 2018 #color(purple)(=> 32 - 72 i # Explanation: #-8i * (9 + 4 i)# #=>-9 * 8 i - 8i * 4i#, removing the bracket. #=> -72i + 32# as #i ^2 = -1# Answer link Related questions How do I multiply complex numbers? How do I multiply complex numbers in polar form? What is the formula for multiplying complex numbers in trigonometric form? How do I use the modulus and argument to square #(1+i)#? What is the geometric interpretation of multiplying two complex numbers? What is the product of #3+2i# and #1+7i#? How do I use DeMoivre's theorem to solve #z^3-1=0#? How do I find the product of two imaginary numbers? How do you simplify #(2+4i)(2-4i)#? How do you multiply #(-2-8i)(6+7i)#? See all questions in Multiplication of Complex Numbers Impact of this question 1377 views around the world You can reuse this answer Creative Commons License