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Really need help! Been trying to solve for a while.

1. Solve the system by using a table. 3y=4x+7 , -4x-4y=28. These are the possible solutions:(–4, –3),(–3, –4), (4, 3),(3, 4).

2.Solve by graphing. -3x-y=-10, 4x-4y=8. possible solutions:(-1,3), (3-1), (1,3), (3,1)

Respuesta :

W0lf93
3y=4x+7 ; 4x - 3y = -7 .... equn 1 
-4x - 4y = 28
  =========
  -7y = 21 ; y = 21/-7 = -3 
 Substituting value of y in equn 1
 4x - 3(-3) = -7
 4x +9 = -7
 4x = -7 -9
 4x = -16
 x = -4 
 Solution : (-4, -3) 
 ------------------------------------- 
 -3x - y = -10 .... equn 1
 4x - 4y = 8 .... equn 2
 =========
 x - 5y = -2 ; x = 5y - 2 
 Substituting value of x in equn 1
 -3(5y - 2) -y = -10
 -15y + 6 -y = -10
 -16y = -10 - 6
 -16y = -16
 y = 1 
 Substituting value of y in equn 1
 -3x - 1 = -10
 -3x = -9
 x = 3 
 Solution : (3,1)

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