Question

solve this equation (x+2) (x+3) + (x-3) (x-2) -2x (x+1)=0

Answer 1

first open the brackets and do the calculations you will get -
x^2 +3x+2x+6+x^2-2x-3x+6-2x^2-2x=0
0=0
hence prooved

Answer 2

firstly open the brackets... then do the calculation...