Question

(Quero com cálculos por gentileza)❤️
1 - Resolva as equações de 2° grau incompletas.

a) x²-6x= 0

b) 7x²-21= 0

c) -x²+5x= 0

d) 2x²-50x= 0

e) 4x²-20x= 0

f) -2x²+14x= 0

g) x²+56x= 0

h) 5x²-50x= 0​

Answer 1

a) x²-6x= 0

x • (x - 6) = 0

x= 0

x - 6 = 0

x= 0 + 6

x= 6

S= ( 0 , 6)

b) 7x²-21= 0

7x² = 0 + 21

7x²= 21

x²= 21/7

x²= 3

x= ± √3

S= ( √3 , - √3)

c) -x²+5x= 0

x • ( - x + 5) = 0

x= 0

- x + 5 = 0

- x= 0 - 5

- x= - 5 ( - 1)

x= 5

S= (0 , 5)

d) 2x²-50x= 0

2x • (x - 25) = 0

x= 0

2x - 50 = 0

2x= 0 + 50

2x= 50

x= 50/2

x= 25

S= ( 0 , 25)

e) 4x²-20x= 0

4x • (x - 5) = 0

x= 0

4x - 20 = 0

4x= 0 + 20

4x= 20

x= 20/4

x= 5

S= (0 , 5)

f) -2x²+14x= 0

2x • ( - x + 7) = 0

x= 0

- 2x + 14 = 0

- 2x= 0 - 14

- 2x= - 14

x= - 14/-2

x= 7

S= ( 0 , 7)

g) x²+56x= 0

x • (x + 56) = 0

x= 0

x + 56 = 0

x= 0 - 56

x= - 56

S= ( 0 , - 56)

h) 5x²-50x= 0

5x² • (x - 50) = 0

x= 0

5x - 50 = 0

5x= 0 + 50

5x= 50

x= 50/5

x= 10

S= ( 0 , 10)