How do you simplify (-1+4i)(-1-4i)? Precalculus Complex Numbers in Trigonometric Form Complex Number Plane 1 Answer J'Neal ยท Stefan V. Apr 10, 2017 17 Explanation: FOIL: 1+4i-4i-16i^2 Subtract: 1-16i^2 i^2=-1 So 1-16(-1) Multiply: 1+16 Add: 17 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 2406 views around the world You can reuse this answer Creative Commons License