Respuesta :

Answer:

  b = -23/16

Step-by-step explanation:

The variable x can be eliminated from the system by multiplying the first equation by -2 and adding that to the second equation.

  -2(-4b +x) +(8b +2x) = -2(7) +(-9)

  16b = -23 . . . . . collect terms

  b = -23/16 . . . .  divide by the coefficient of b

The value of b is -23/16 = -1 7/16.