Solving Simultaneous Equations

1. Work out the values of N and M(1) 8m+ 4n = 104(2) 8m + 2n = 1342n = -30n = -15(1) 8m + 4(-15) = 1048m - 60 = 1048m = 164m = 20.5(2) 8(20.5) + 2(-15) = 134164 - 30 = 104N = -15M = 20.52. Work out the values of A and B(1) 3a + 4b = 14(2) 4a + 2b = 2(2 x2) 8a + 4b = 4(1) 3a + 4b = 145a = -10a = -2(1)3(-2) + 4b = 14-6 + 4b = 144b = 20b = 5(2)4(-2) + 2(5) = 2-8 + 10 = 2A = -2B = 53. Work out the values of X and Y(1) 5x + 2y = 26(2) 8x - 4y = 20(! x2) 10x + 4y = 52(2) 8x - 4y = 20[Add Equations Together as one is -4 and the other +4]18x = 72x = 4(1)5(4) + 2y = 2620 +2y = 262y = 6y = 3(2)8(4) - 4(3) = 2032 - 12 = 20x = 4y = 3

Substitution Method

1. Solve for X or Y in one equation2. Plug into other and solve3. Use that value to solve for the other variable