How do I factor x^2+4x+20

Question

Isaias Watkins

Mathematics

20 February, 17:09

How do I factor x^2+4x+20

+3

Answers (1)

Know the Answer?

Sam Hicks · Answer 1

Its like x² + 4x + 20 = 0,

x = [-4 + √[ (4²) - (4*1*20) ]] / (2*1) = [-4 + √ (16-80) ]/2 = [-4 + √ (-64) ]/2 = [-4 + 8√ (-1) ]/2 = - 2 + 4i,

x = [-4 - √[ (4²) - (4*1*20) ]] / (2*1) = [-4 - √ (16-80) ]/2 = [-4 - √ (-64) ]/2 = [-4 - 8√ (-1) ]/2 = - 2 - 4i,

here i = √ (-1), its a complex number.

so solution is a complex number,

x = - 2 - 4i & - 2 + 4i.