1)√5x-9=65x-9=365x=36+95x=45x=45/5x=9проверка:√5*9-9=6√36=66=62)√x^2+4x-5=4x^2+4x-5=16x^2+4x-5-16=0x^2+4x-21=0Д=16-4*1*-21=16+84=100x1=-4+10/2=6/2=3x2=-4-10/2=-14/2=-7проверка:1) √3:2+4*3-5=4√9+12-5=4√16=44=4 2) √49+4*-7-5=4√49+28-5=4√72=4 - не подходит3)√2x^2+2x=√-x-12x^2+2x=-x-12x^2+2x+x+1=02x^2+3x+1=0Д=3^2-4*2*1=9-8=1x1=-3+1/4=-2/4=-1/2=-0.5x2=-3-1/4=-4/4=-1проверка:1) √2*-0,5^2+2*-0.5=√0.5-1√2*0.25+1=√0.5-1√1.5=√-0.5 - не подходит2) √2*-1^2+2*-1=√1-1√2*1-2=√1-1√0=√0