Question

Why equals 3/4 X -12 and why equals negative 4X - 31

Answer 1

Answer:

  (x, y) = (-4, -15)

Step-by-step explanation:

Perhaps you want the solution to ...

  y = 3/4x -12

  y = -4x -31

Equating the two expressions for y gives ...

  3/4x -12 = -4x -31

  3/4x = -4x -19 . . . . . add 12

  3x = -16x -76 . . . . . multiply by 4

  19x = -76 . . . . . . . . . add 16x

  x = -76/19 = -4 . . . . divide by 19

  y = (3/4)(-4) -12 = -15 . . . . use the first equation to find y

The solution to this system of equations is ...

  (x, y) = (-4, -15)