Question

operacion cuadratica metodo de factoreo:

x^2-7x-20=0

ayuda plizz

Answer 1

$x^{2} -7x-20=0 \\ de la forma: \\ a x^{2} +bx+c=0 \\ factoriza: \\ x= \frac{-b+ \sqrt{} b^{2}-4ac }{2a} \\ x^{2} -7x-20=0 \\ x= \frac{-(-7)+ \sqrt{ (-7)^{2}-4(1)(-20) } }{2(1)}= \frac{7+ \sqrt{49+80} }{2} = \frac{7+ \sqrt{129} }{2} \\ o \\ x= \frac{-(-7)- \sqrt{ (-7)^{2}-4(1)(-20) } }{2(1)}= \frac{7- \sqrt{49+80} }{2} = \frac{7- \sqrt{129} }{2} \\ factoriza como: \\ (x-(\frac{7+ \sqrt{129} }{2}))(x+(\frac{7- \sqrt{129} }{2}))=0 \\ o \\ Decimal: \\ (x-9.18)(x+2.18)=0$

otra forma:
x²-7x-20=0
x²-7x+(49/4)-(49/4)-20=0
(x-(7/2))²-129/4=0