Question

8) 20 - (x + 5) = 3(x - 3)
9) 18 + (x - 4) = 5(x + 1)
10) (x + 6)(x + 3) = x(x + 8) - 3​

Answer 1

Respuesta:

8 ) x = 6

9 ) x = 9 / 4

10 ) x = - 6

Explicación paso a paso:

8 )

20 - ( x + 5 ) = 3 ( x - 3 )

20 - x - 5 = 3x - 9

20 - 5 - x = 3x - 9

15 - x = 3x - 9

15 + 9 = 3x + x

24 = 4x

x = 24 / 4

x = 6

9 )

18 + ( x - 4 ) = 5 ( x + 1 )

18 + x - 4 = 5x + 5

18 - 4 + x = 5x + 5

14 + x = 5x + 5

14 - 5 = 5x - x

9 = 4x

x = 9 / 4

10 )

( x + 6 ) ( x + 3 ) = x ( x + 8 ) - 3

x ( x + 3 ) + 6 ( x + 3 ) = x^2 + 8x - 3

x^2 + 3x + 6x + 3 = x^2 + 8x - 3

x^2 + 9x + 3 = x^2 + 8x - 3

x^2 - x^2 + 9x - 8x = - 3 - 3

0 + x = - 6

x = - 6