How do you find abs(-3 - 4i )? Precalculus Complex Numbers in Trigonometric Form Complex Number Plane 1 Answer Eddie Jun 28, 2016 5 Explanation: for z = a + i b, |z| = \sqrt{a^2 + b^2} here |z| = sqrt[(-3)^2 + (-4)^2] = 5 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 1462 views around the world You can reuse this answer Creative Commons License