How do you find abs(-8-4i)|−8−4i|? Precalculus Complex Numbers in Trigonometric Form Complex Number Plane 1 Answer Ratnaker Mehta Aug 18, 2016 |-8-4i|=4sqrt5~=8.9444|−8−4i|=4√5≅8.9444. Explanation: For, z=x+iy in CC, |z|=sqrt(x^2+y^2). Hence, |-8-4i|=sqrt((-8)^2+(-4)^2)=sqrt(64+16)=sqrt80=sqrt(4^2*5)=4sqrt5. Taking, sqrt5~=2.2361, Reqd. Value~=4*2.2361=8.9444. Answer link Related questions What is the complex number plane? Which vectors define the complex number plane? What is the modulus of a complex number? How do I graph the complex number 3+4i in the complex plane? How do I graph the complex number 2-3i in the complex plane? How do I graph the complex number -4+2i in the complex plane? How do I graph the number 3 in the complex number plane? How do I graph the number 4i in the complex number plane? How do I use graphing in the complex plane to add 2+4i and 5+3i? How do I use graphing in the complex plane to subtract 3+4i from -2+2i? See all questions in Complex Number Plane Impact of this question 1523 views around the world You can reuse this answer Creative Commons License