How do you find the absolute value of the complex number z= 2 + 5i? Precalculus Complex Numbers in Trigonometric Form Multiplication of Complex Numbers 1 Answer Steve M Jan 11, 2017 # |z| = |2 + 5i| # # \ \ \ \ = sqrt((2)^2+(5)^2) # # \ \ \ \ = sqrt(4+25) # # \ \ \ \ = sqrt(29) # 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 6843 views around the world You can reuse this answer Creative Commons License