Question

Pfvr me ajudem preciso mto

Answer 1

Resposta:

a) x² - x - 20 = 0

delta= 1² -4.1.(-20)

delta= 1+80

delta= 81

x= 1 -+ raiz de 81 / 2.1  

x'= 1+9/2

x'=10/2

x'= 5  

x"= 1-9/2

x"=-8/2

x"= -4

(5,-4)

b) x² - 3x -4 = 0

delta= (-3)² -4.1. (-4)

delta= 9+16

delta=25

x= 3+-raiz de 25/2

x'= 3+5/2

x'= 8/2

x'=4

x"= 3-5/2

x"= -2/2

x"= -1

(4, -1)

c) x² - 8x + 7 = 0

delta=(-8)² -4.1.7

delta= 64-28

delta= 36

x=8+-raiz de 36/2

x'= 8+6/2

x'= 14/2

x'=7

x"= 8-6/2

x"=2/2

x"=1

ESPERO TER AJUDADO!!!! :)