Question

ME AJUDEM !!!
Determine as soluções das equações
a) 3x² + 5x = 0
b) 5/4 x² - x = 0
c) x² = 7x
d) 4x² - 12x = 0
e) 4/3 x² - 3 = 0
f) - 2x² + 10x =0

Answer 1

a) 3 x² + 5 x = 0
x(3 x + 5 ) = 0
x = 0
3 x + 5 = 0
3 x = -5
x = -5/3
S = {0,-5/3

b) 5/4 x² - x = 0
x(5/4 x - 1 ) = 0
x = 0
 5/4 x - 1 = 0
5/4 x = 1
x = 1 : 5/4
x = 1 . 4/5
x = 4/5
S = {0,4/5 }

c)x² = 7 x
x² - 7 x = 0
x( x - 7 ) = 0
x = 0
x - 7 = 0
x = 7
S = {0,7}

d) 4x² - 12 x = 0
4 x(x - 3 ) = 0
4 x = 0
x = 0/4
x = 0
x - 3 = 0
x = 3
S = {0,3}
e) 4/3 x² - 3 = 0
4/3 x² = 3
x² = 3 : 4/3
x² = 3 . 3/4
x² = 9/4
x = \/9/4
x = 3/2
S = {0 , 3/2}

f) -2 x² + 10 x = 0
2 x( - x + 5 ) = 0
2 x = 0
x = 0/2
x = 0
-x + 5 = 0
-1 x = - 5
x = -5/-1
x = 5
S = {0,5 }