Question

A)7x²-x=0(R:0 e 1/7
B) 2x²=7x(R:0 e 7/2
C) 2x²=8x(R: 0 e 4 )
D) 7x²= -14x (R: 0 e -2)
E) -2x²+10x=0 (R: 0 e 5)

Preciso de respostas urgentes

Answer 1

A) 7x² - x = 0

x (7x - 1) = 0
x = 0

7x - 1 = 0
7x = 1
x = 1/7

s={ 0, 1/7 }
.
.
.
B) 2x² = 7x

2x² - 7x = 0

x (2x - 7) = 0
x = 0

2x - 7 = 0
2x = 7
x = 7/2

s={ 0, 7/2 }
.
.
.
C) 2x² = 8x

2x² - 8x = 0

x (2x - 8) = 0
x = 0

2x - 8 = 0
2x = 8
x = 8/2
x = 4

s={ 0, 4 }
.
.
.
D) 7x² = -14x

7x² + 14x = 0

x (7x + 14) = 0
x = 0

7x + 14 = 0
7x = -14
x = -14/7
x = -2

s={ 0, -2 }
.
.
.
E) -2x² + 10x = 0

x (-2x + 10) = 0
x = 0

-2x + 10 = 0
-2x = -10
x = -10/-2
x = 5

s={ 0, 5 }





☆Espero ter ajudado! tmj