Question

x ao quadrado + 19 x - 120 = 0

Alguém sabe ?

Answer 1

X² + 19 x - 120 = 0

Δ=19²-4.1.(-120)
Δ=361+480
Δ=841

X=-19±√841/2.1
X=-19±29/2
X'=-19+29/2=10/2=5
X"=-19-29/2=-48/2=-24

S={5,-24}

Answer 2

${x}^{2} + 19x - 120 = 0 \\ x = \frac{ - b\frac{ + }{} \sqrt{ { (b)}^{2} - 4.a.c} }{2.a} \\ x = \frac{ - 19\frac{ + }{} \sqrt{ { ( 19)}^{2} - 4.1.( - 120)} }{2.1} \\ x = \frac{ - 19\frac{ + }{} \sqrt{ 361 + 480} }{2} \\ x = \frac{ - 19\frac{ + }{} \sqrt{841} }{2} \\ x = \frac{ - 19\frac{ + }{} 29}{2}\\ x = \frac{-19 + 29}{2}\\ x= \frac{10}{2} =5\\x = \frac{-19-29}{2}\\x=\frac{-48}{2}=-24\\ \\ S=(5, -24)$