Question

Resova as equações:
a) x*2 + 5x=0

b)x*2+6x+9=4

Answer 1

a)2x+5x=0
7x=0
x=0/7

b)2x+6x+9=4
2x+6x=4-9
8x=-3
x=-3/8
Espero ter ajudado ;)

Answer 2

a) x2 + 5x = 0
x(x + 5) = 0
 x= 0
x + 5 = 0
x =  - 5
 S = { 0 ; - 5 }
b) x2 + 6x + 9 = 4
x2 + 6x  + 9 - 4 = 0
x2 + 6x + 5 = 0
a = 1 , b = 6 e c = 5
delta = b2 - 4a.c
delta = (6)2 - 4 . 1. 5
delta = 36 - 20
delta = 16
x = - b + - Vdelta / 2a
x = - ( + 6)  + - V 16 / 2.1
x' = - 6 +  - 4 /  2
x' = - 6  - 4 / 2
x' = - 10 / 2
x' =  - 5
x" = - 6 + 4 / 2
x" = - 2 / 2
x" = - 1
S = { - 5 ; - 1 }