a)2√108+x=√12
12√3+x=2√3
12√3-2√3=-x
10√3=-x =>x=-10√3
b)√200-x=√162
10√2-x=9√2
10√2-9√2=x =>x=√2
c)2√3(x√3+1)=5x+√12
6x+2√3=5x+2√3
6x-5x=0 =>x=0
d) (x+√2) (√3+√2)=2x√3+x√2+7
x√3+x√2+√6+2=2x√3+x√2+7
x√3-2x√3=7-2-√6
-x√3=5-√6
x√3=√6-5 =>x=(√6-5)/√3=√3(√6-5)/3=(3√2-5√3)/3
