What is the easiest way to solve a simultaneous equation?

While the elimination method can be extremely easy for certain questions, it cannot be applied to all. Therefore, the substitution method is recommended because it can be applied to most cases of simultaneous equations. Take, for example: xy=2 and y=x+1. Here elimination does not work but with substitution one can solve easily for x and y as shown below:
if y=x+1 then x(x+1)=2 x^2+x=2This can be manipulated into a quadratic equation: x^2+x-2=0(x+2)(x-1)=0Therefore x=-2 or x=1Simply reinsert these x-values back into one of the original equations (both if you want to be certain)when x=-2 y=-2+1Therefore (-2,-1)Or, when x=1 y=1+1Therefore (1,2)