Question

9 (3х+5) +5 = 2 (x-5)²
3x² — 11х + 10 = 0
2x²-5x=0​

Answer 1

9*3x+9*5+5=2(x²-2*x*5+5²)
27x+50=2x²-20x+50
2x²-20x-27x+50-50=0
2x²-47x=0
△=47²-4*2*0=47²
x1=(47+47)/(2*2)=94/4=47/2
x2=(47-47)/(2*2)=0


3x²-11x+10=0
△=11²-4*3*10=121-120=1
x1=(11+1)/(2*3)=12/6=2
x2=(11-1)/(2*3)=10/6=5/3


2x²-5x=0
△=5²-4*2*0=25
x1=(5+5)/(2*2)=10/4=5/2
x2=(5-5)/(2*2)=0