Algebra

Its called the art of guessing elmer

We know that X1 is equal to the √5-2. So we insert this for "x" in the equation x^2+ mx+n=0. Resulting in (√5-2)^2+m(√5-2) + n=0

We then take off the brackets: 5-4√5+4+m√5-2m+n=0 becomes our result We can then use reverse distributive property and group the equations in a different way such that the terms can be both equal to 0. √5(m-4)+(5+4-2m+n)=0

√5(m-4)=0 and 9-2m+n=0

Therefore m=4 and n=-1

So m+n=3