Question

*VALENDO 100 PONTOS!!!*

64x²-25=0
9x²-45=0
49x²-9=0
(x-3) (x+4) +8=x
(x+2) x=2 (x+8)
x (3x-1) =18-x
(x+2) (x-2) =-2
2x (x-1) =2 (8-x)

Answer 1

64x²-25=0

64x²= 25

x²= 25/64

x= ± √25/64

x= ± 5/8

S= ( 5/8 , - 5/8)

9x²-45=0

9x²= 45

x²= 45/9

x²= 5

x= ± √5

S= ( √5 , - √5)

49x²-9=0

49x² = 9

x²= 9/49

x= ± √9/49

x= ± 3/7

S= ( 3/7 , - 3/7)

(x-3) (x+4) +8=x

x² + 4x - 3x - 12 + 8 = x

x² + x - 4 = x

x² + x - x - 4 = 0

x² - 4 = 0

x²= 4

x= ±√4

x= ± 2

S= (2 , - 2)

(x+2) x=2 (x+8)

x² + 2x =2x + 16

x² + 2x - 2x - 16 = 0

x² - 16 = 0

x²= 16

x= ± √16

x= ± 4

S= ( 4 , - 4)

x (3x-1) =18-x

3x² - x - 18 + x = 0

3x² - 18 = 0

3x²= 18

x²= 18/3

x²= 6

x= ± √6

S= ( √6 , - √6)

(x+2) (x-2) =-2

x² - 2x + 2x - 4 = - 2

x² = - 2 + 4

x²= 2

x= ± √2

S= ( √2 , - √2)

2x (x-1) =2 (8-x)

2x² - 2x = 16 - 2x

2x² - 2x + 2x - 16 = 0

2x² - 16 = 0

2x²= 16

x²= 16/2

x²= 8

x= ± √8

S= ( √8 , - √8)

Answer 2

Resposta:

100-20x40=80 coreto e 80 - 100 = 20