Solve the simultaneous equations: 4x + 7y = 1, 3x + 10y = 15.

4x + 7y = 1 1. 3x + 10y = 15  2. 1. x 3 (4x x 3) + (7y x 3) = 1 x 3                       12x + 21y = 3  3. 2. x 4  (3x x 4) + (10y x 4) = 15 x 4                         12x + 40y = 60  4. 4. - 3.  (12x - 12x) + (40y - 21y) = 60 - 3                                            19y = 57                                                y = 57/19                                                y = 3 Sub y into 2.  3x + 10(3) = 15                           3x + 30 = 15                                 3x = 15 - 30                                    3x = -15                                      x = -15/3                                      x = -5 y = 3, x = -5        

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