Solve the simultaneous equations 3x + y = –4 and 3x – 4y = 6

  1. Label first equation as equation 1 and the second as equation 22) Make y the subject of the equation from equation (1); hence: eq 1 : y = -4 -3x3) Substitute the new equation into equation (2) : 3x- 4(-4-3x)=6 --> 3x+12x +16=64) Collect like terms : 15x = -10, so x = -2/3 5) Substitute calculated value of x into any of the original equations to find y, hence y= -2
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