Solving simultaneous questions, e.g. 3x + y = 11 and 2x + y = 8
The unknowns in a simultaneous equation need to be solved, which in this case are x and y.The method I will be using is by elimination:First, find which unknown has the same coefficient. In this example this is the letter y that has a coefficient of 1 in both equations.Then, subtract the two equations from each other to eliminate y so you get:3x + y = 11-2x + y = 8-------------x = 3Now, you know what x is so you can substitute x back into any of the equations to rearrange and find yIn this case subbing into 3x + y = 113x + y = 113(3) + y = 119 + y = 11y = 2We have now found x = 3 and y = 2To check the answers are right, substitute this back into the second equation just for confirmation and this should work!
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