Question

Resolva as Equações do 2° Grau

A) X²-6x-40=0
B) 2x²-8=0
C) x²-23x+60=0
D) x²-x=0

Answer 1

vamos lá.....

a) x²-6x-40 = 

6+-√36-4(1)(-40)/2

6+-√36+160/2

6+-√196/2

6+-14/2

x' (6+14)/2 = 8

x'' (6-14)/2 = -4

b) 2x²-8 = 0
 
   2x² = 8
  
  x²= 8/2

x² = √4
x =+-2

c) x²-23x+60 = 

23+-√529-4(1)(60)/2
23+-√529-240/2
23+-√289/2
23+-17/2

x' = (23+17)/2 = 20

x'' = (23-17)2 = 3

d) x²-x= 0
    x(x-1)= 0
   x = 0
 x-1 = 0
  x= 1