Solve the simultaneous equations: 3x + y = 19 and x - 2y = -3

First rearrange x - 2y = -3 by adding 2y to each side to give x = -3 + 2ySubstitute this into the first eq. to give 3(-3 +2y) + y = 19Expand brackets first: -9 + 6y + y = 19Rearrange and simplify by collecting the y terms and adding 9 to both sides, so terms of y are on one side and numbers on the other: 7y = 28Divide both sides by 7 to get y = 28/7 = 4Substitute y = 4 into the equation for x to find the value of x: x = -3 + 2y = -3 + (2*4) = -3 + 8 = 5x=5, y = 4

JM

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